Built up crosman pistol would be the smallest/lightest, IF you can live with a 12" barrel and huge jet blast of wasted air 40fpe would be easy with a few shots the same, 50fpe easy if you can use a short Korean style "curve" ( down). After that the out of production ( and rather rae even then ) Career 707 II pistol. Yes they made one and sold in the US. An honest 60fpe with something like a 34g pellet in .22, honking heavy but short. I've fired a couple of different Theoben pistols that shot 1/2" at 50 yards at 12-16fpe and if changed to .22 would easily hit 30+fpe. and do what you want. If you could find an RWS2000 aka FX ????, Excalaber ? it would be under your price range and 100% capable.
John