Sweet. Gotta like stores that purchase old car parts and sell them.
In college, I used to have a 1960 Mercury Commuter wagon. Same one Fred McMurry drove in Flubber (I am sure you remember.) What a beast - aqua paint and vinyl, 4 door pillarless coupe, flat tail fins, oval taillights laid over at a 45 degree angle, huge wrap around side windows, underdash AC, what a car. Had a 383 engine which everyone tried to tell me was a 390 and sold me part after part that didn't fit. Apparently the 383 engine was not in their books.
Stumbled into a warehouse parts store in downtown Tulsa. Small, poorly lit, grimy, greasy, and chock full of factory parts still in the old original packages. Parts straight out of the cold war era. Those people must have had every obscure part in the book. Don't remember the name, but will look it up if anyone needs it.
Only people that I ever met that recognized the 383.