Bro,
IMHO, H22A injector is recommended along with VAFC. If i'm not mistaken, there's B20 high compression piston (85mm,again if i'm not mistaken, its a TODA piston...well, at least its written there in the AMOIL webpage, not sure whether its really TODA's ) selling at Amoil.
Porting, balancing,boring, bearings...all wouldn't be cheap...your 5k is definitely not enough for all this...