1) Charger in the 20 to 25USD range - There are 3 brands mostly recommended, (lower end) Nitecore, (middle ground) Efest, and (top end) Xtar. All 3 brands make good, intelligent chargers, where Nitecore covers just the basic features needed, Efest (LUC and BLU lines) add in extra features like manually setting of charge rate (.5amp, 1amp, 2amp), Xtar lines are the Cadillacs with similar fashion of both an Efest or Nitecore (charge rates at 0.25, 0.5, and 1amp) they also carry the strongest of warranties. You can if you look around find Nitecore i2 and i4 chargers for under the 20USD range, Efests for the LUC2 and LUC4 can start in the 25USD range, Xtar with such a wide range you can probably find a good 2bay in the 25USD range. That said, with your mod being a 2 or 3 battery mod, you'll want a 4bay anyway for those times you need 3 batteries charged, the extra bays come in handy, so I'd suggest any of these 3 models to start, the Nitecore i4, Efest LUC4, or Xtar VC4.
2) Batteries - I do not know if you are running that Wismec 2/3 in dual or triple battery configuration, if triple battery @2000mah and 80watts you should be seeing almost a day and a half to 2 day run time, sounding like you have LG HD2 or HD4 batteries which are 25amp CDR batteries that mod would need if you went closer to max watts on it at lowest battery charge level, if dual battery you should be seeing 3/4 to 1 1/2 day run times otherwise. If you are staying inbetween 80 to 150watts though, and needing some extra Mah but still at 25amp CDR, the Sony VTC5A 2500mah battery might suit your needs a lot better. But if you don't ever go past that 80watt mark, a 3000mah battery like the Samsung 30Q, Sony VTC6, and the LG HG2 would suit your criteria a lot better though they are 20amp CDR batteries category.
Watts Formula for regulated mod CDR requirements (Watts Set/Lowest Battery Shutoff Point/Mod Efficiency=Max Amps)
Dual Battery
80Watts/6.4v (3.2v per battery)/90% Mod Efficiency = 13.8889amps both batteries have to support
Triple Battery
80/9.6/90% = 9.2593amps all three batteries have to support.
A mod with better battery life, that is all relative to the wattage being used, battery Mah, as well as type of battery (internal LiPo vs 18650), battery configuration (single, dual battery series, dual battery parallel, triple battery series, quad battery series, etc), your 2/3 is a series configuration dual or triple battery thus its 2/3 naming, 2 or 3 batteries, with series voltage is multiplied by X number of batteries though the Mah and CDR stay the same of a single battery, where parallel configurations you get the voltage of a single battery, and Mah is multiplied by X number of batteries, theoretically CDR is X number of batteries also but we suggest 50% plus per extra battery for safety purposes. Control board efficiency also plays a minor part, as the board takes power out to function itself, so if a board takes 10% of battery power to function, you get a 90% rating of efficiency and finally what hits the coils of you tank/atomizer, as well as technically 90% of your mah runtime on your batteries. A good mod to look at you might try any mod with a DNA166 or DNA200 control board being these boards by spec sheets are 98% efficient, though they can be pricey, after that I'd look at a RX200/RX200S, or even an RX300 by Wismec if you been happy with your Wismec thus far.
To calculate your Watt Hours you have the formula is such
Nominal Voltage = Voltage Rating of the Battery, in the case of an 18650 that is 3.7v
Mah X Nominal Voltage/1000= Watt Hours
2000mah X 3.7v/1000=7.4watt hours per battery with the batteries you have, with your 2/3 in dual battery mod would 14.8 watt hours, triple battery configuration should be 22.2 watt hours
May leave you with more questions than answers but you are kinda vague to begin with on information, and if you are definitely getting less than 3/4 to a full day of runtime from your mod, get new batteries first, this is generally the deciding factor that is noticable of them going toward the end of their lifetime, their decrease in runtime and they run hotter than they used to brand new, if you are still having bad run time with new batteries, then there is a malfunction going on in your mod draining your batteries more than it should, 80 watts on a single battery would roughly give you about 2 to 3 hours run time, dual battery that would equate to 4 to 6hours runtime, triple battery 6 to 9 hours runtime, these are rough approximate figures, if you are using it constantly every moment of the day will also affect that run time, my figures are for using the mod every 20 to 30minutes or so for 5 to 10 puffs.
