Seat Foam Questions - 1965 Eldorado w/buckets

[skinny_tom]

My buckets were recovered years ago in almost-stock looking vinyl. The foam got all dry and crumbly while it sat and now, since this isn't a restoration project, I'd like to replace the foam and reuse the perfectly good vinyl until the money for leather comes along.

Problem is, I can't find foam for a "1965 Cadillac Eldorado bucket seat." Everything is listed for other GM makes, some of which are likely the same seat. My body service manual shows "4-way Bucket Seat for 35 - 36 - 38 - and 68000 Series." I don't know what the other series GM makes are and Google is not cooperating this afternoon. (Or maybe I'm not patient enough to sort through the 10,000 results when this group has always been so helpful.)

I imagine there's a match with another GM bucket seat. Anyone know which one that is?