Marty,
They look a lot like 60's Mustang latches, but I have no idea if the size matches.
https://www.ebay.com/itm/1965-1966-1...-/143540690083
https://www.adamscc.nl/nl/67-68-trap-door-latch-fb
But, getting 15 could be quit costly.
Unless you are able to find the original item, I would indeed look at making your own. There is a number of firms here in Holland that supply folded profiles on demand...that should give you the Omega-profile. The remainder could be done with simple hand tools and some elbow grease. Springs from Amatec, or an online source.
Alex