Factory SBC V8 in a 64? Nope, not factory. 1967 was the first year for a V8 and that was a 283 (early in the year) or 307. 307 1968 and newer, though there are some reports of a 350 being available in some few vans from late 1969 through mid-year 1970 when 2nd gen production ceased. That said the 1969 Chevy and Sportvan sales brochure I have only shows a single 200HP 307 V8 option
First v8 was a 283 available in 67...... This van has great potential for somebody who prefers no side doors (not me!)..... The price doesn't work for me, but it may for the next guy....