[vettestr]

Hello Mark,
Congrats on your first post and welcome. Your ? about engine size is a loaded or difficult answer. What is just enough for one is too much or too little for another so maybe better to describe what you want. A streetable engine for some is no trade offs or need for anything but gas and go. An un-streetable engine for the same guy is loading up if idled much, need to adjust many things like the valve / rocker clearance and so much more.
Welcome to the addiction of these cars and enjoy your toy!!!!! It might be a good idea to define what you will do with or want out of your cars engine and do you have much experience driving and wrenching on high HP to weight ratio cars? Even a zillion cubic inches can be tame and streetable until you push the crazy pedal and a very tame small cubic inch engine can get away from you if pushed. There is a happy place in all choices but a lot cheaper to buy what you really want the first time so do a little homework. Hang with some other cars in your area to help with your direction.