Smallest I ever found for stock general's for the rear wheel was 40.. from Handy Bikes which is no more.. if you can get a 40, you're probably running 11 drive which is a gear ratio of 3.63 - which is pretty good - some people would say that's the best for V1's..
Next solution, get a different rear wheel.. one that allows for smaller sprockets.. I've never taken that route, maybe someone can chime in on wheels they've used successfully (maybe used a different swingarm or just shimed it?) (I feel like a morini wheel works... I think that's what someone I know used.. Pacer wheel too.. and lastly unconfirmed but Tomos A35 sprockets will fit on some Italian wheels)
Also, you could find a 12 drive sprocket and depending on what your stock rear is that might get you closer to where you want to be.. anything between 42 to 44 would get you 3.5 to 3.6+..
Lastly.. find a weird sprocket on Ebay with and ID smaller than the General and enough material for a new bolt pattern.. find a machinist to throw it on a lathe.. viola.. (can be pricey unless you're hooking up with the machinist)
Here is a link to an old thread about V1 gear ratio's: