Paleontology/museum person here! These do look like catalog numbers that would be written on a specimen from a museum, university research collection, etc. Kind of like the Dewey decimal system numbers for library books. The format is a little unusual, but normally the letters that start off the bottom line would be the institution’s acronym. CEU could stand for the College of Eastern Utah, which does have the Prehistoric Museum in Price, Utah.
The cast (it is a cast, I can see air bubbles and can tell by the paint job) does look to be of a “raptor” big toe claw. Nice find! If you’d like more information about it I’d say reach out to the CEU Prehistoric Museum and ask. Or, if you’d like, I can look and see if I can make any contacts there through my work. I don’t know anyone there personally but it’s a small world!
Forever seeking: Blackwatch the raffle Old Warrior, Jennifer Miller's pieces, and GB Baby unis!