I ordered a set of pins, inserts, and plates for my OPR four years ago, and Shopsmith had everything in stock at the time. I ran those part numbers through their search box just now, and it appears that they still carry them as service parts.
There were different versions of the table, so your inserts may be different than mine. There are pics of mine in the post below. The “pin insert” isn’t shown, but it just mounts to the black table plate in place of the insert with the router-bit clearance hole. The pin insert has a threaded hole in the center, into which you can mount any of three different diameters of guide pins.https://www.shopsmith.com/ss_forum/view ... 41#p213741