the one thing I regret in my latest 350 build was NOT going the 383 route. i too was trying to doing a budget friendly build, started with a junkyard 350. tore down, found similar things. bores nothing good shape, bearings not great. etc. ended up buying pistons and rods and getting the stock crank polished and balanced. i also think for anyone going the flattop piston route to just get forged pistons. i went the cast route and they are fine, but the added detonation resistance would have been nice. i also went through a set of TBI heads. while this had been a "dream" of mine to see what these heads could do with a little work I would 100% go aluminum w/ modern style chamber. I think you posted an aluminum knock-off of the vortec style head? this is the route I would go for a "budget" build for sure.
as far as your transmission.... is it in relatively good shape? I can help you with a DIY shift kit that will extend the life of the trans if you are worried surviving behind. I know
@L31MaxExpress doesn't like them, but i think his gas pedal is an on/off arrangement only, HAHA.