Steve, great detective work!!
1961088 is the correct one (62-69 6 cylinder), but it was superceeded by the 1852935 in January of 1976, so finding one is going to be next to impossible.
The problem is finding the "correct" style. CLARKS CORVAIR
shows the wick for the Corvair (same P/N by the way), on page 77 (item number 10), but there's a little asterisk next to the part, so I'm not sure if it's "right". Joe, you might want to give them a call.
However, I just spoke to Jeff at CALIFORNIA CORVAIR
(a friend of mine) and he said he probably has a few used ones. Would that work for you Joe?