Don Y wrote:
Something like this:

http://ecx.images-amazon.com/images/I/417-rr-7-QL._AC_UL320_SR168,320_.jpg

But with a much deeper recess/setback for the keystone insert.

(Also prefer NOT to have the protruding "rivets")

That's a wall plate for a telephone isn't it ? The "rivets" engage keyhole
slots on the back of the phone ...

--
Snag