Source of Polarized Cheater Cords??

[Bruce Brackin]

Looking for several polarized tv style cheater cords.  Looking for type
with 2 mounting holes (~3/16" dia and ~ 15/16" on center) for attaching
cord to back panel.   Antique Electronics has nice non-polarized cords
and carries chassis jacks for both.  No luck with "usual sources".
Redoing 3-4 AC/DC sets and would like to swap to polarized in rebuild
process.  Also looking for the hollow "rolled rivets" to fit as well.

Thanks - Bruce, KD5IUG