I have a Polish Underfolder rear trunion, used but in very nice condition. It is parkerized, and has no grinding marks on it. It is a take-off from a parts kit (I ended up with an extra one from a build where I put a solid stock on in place of an underfolder). Price is $50 shipped for this otherwise elusive part that some parts kits don't come with.
Sold Pending Funds to IHC53