Are these wheels stock? Wanting to order caps...

[vikingsandpintos]

I got these wheels from somebody, but don't know anything about them. My daughters truck is a 67 C10, with 6 lug wheels. I got these used, but they didn't come with center caps or hub caps, and would like to get some. But I'm not sure if these are stock for this truck, or something else. I was going to order some repo caps, but was hoping somebody could tell me if I order caps for a 67, if they will fit these wheels?

The ridge in the wheel near the lug nuts has 3 bumps, I am pointing to one in the pic. The other side of that ridge on the tire side is smooth all the way around. Any info is appreciated!