hey mate
You could use a toyota sc14 as u could pick up one of thes and pully for round $400 create brackets your self, ither get a 4 barrel holly or quadrajet set up for a blow throo set up or call caslemain rod shop, and order one of ther 350 holley draw throo adaptors or get one custom made, im curently runing one on a 202 and if this motor gives up the gost iv got a small camed 30thow ova 253 im going to do the same.
My nabours son has a hz gts with a completly built 253, borded out, vn heads, manifold not to shore if its carby or inj have to ask again, and twin sc14's runing the standard clutch set up with a custom crank pully at 8 pound it makes 300kw.
should give it a kick in the rear cheers