Name & Source for M7 Grip Screw Inserts?

[boodie]

I'm doing a couple sets of "retro" grips for the M7. I'm using brown Delrin, and it works very nicely on the lathe/mill. (Pic attached).

But it's soft, so I want to use the flanged nut/sleeve like the OEM M7 grips (and screw, too).

I checked the Jantz and Texas Knifemakers catalogs and don't see this type.

What exactly are they called, so I can search for them???

And if anyone knows a source, I'd appreciate it!