Stock wheel middle Jeep pop in insert

Hey, I have that little pop in thingy missing on one of my wheels (original stock '98 classic). I know, it's just cosmetic; but I'm a nuke engineer kinda guy and it just bugs the snot out of me everytime I see her from the side with that wheel. Tried googling but:
1. What is that silly thing called?
2. Anyone know where to get one other than scrounging junkyards?

Center cap or center wheel insert

Search ebay for Jeep center cap.

It might be best to measure one of the ones you stil have so you can narrow down the options. I see several different sizes available.

Anak said:

Search ebay for Jeep center cap.

It might be best to measure one of the ones you stil have so you can narrow down the options. I see several different sizes available.

Click to expand...

And look closely at the pictures. Pay attention to the tabs on the inside.
What wheels anyway?