if you want a lil more power for stunting a 70kit that uses stock head is a good option, about $100 reuse stock carb. if you can find a cheap used xr70 carb the 82 kit is another low buck option. then you have all your 88kits out there. just depends on how much you want to spend.
My daughter's bike has a mildly ported FPM E22 with matching cam, a CHP 88 kit, BBR exhaust, 4spd w/auto, and a Shengway 18mm carb and she can hole shot all the little Katoom 2smokers in her class taking off in 3rd gear.....no poo.....get a little FirePower in your mini