ARG! Factory tank carpet with copper/brass rivets?

[davepl]

I am restoring a 1970 GMC Sierra Grande that is equipped with factory buckets. The tank carpet with buckets has a number of brass/copper oval rivets that allow it to screw into the body.

Like an idiot, I didn't stop to think this might be hard to replace, and did not keep the original.

Many reproductions I’ve seen lack this, and clip to the tank in some manner. I don’t know if the rivets were only for bucket seat trucks, but that’s what I’m looking for. Anyone know if (a) that's specific to the bucket seat trucks and (b) if anyone makes a proper reproduction?

Thanks!
Dave