They are probably going to have to be pulled from another dead amp which may have used the same ones.
Got a tickle in me brain on this and sure enough, the same post is used by Bryston. Which plans to be around for a long time and probably has a large supply.
Call them up and they may be able to communicate the brand to you and help source a replacement or supply a replacement to you.
Otherwise you’ll be lost in the woods for weeks..... and maybe never get out.
Look at the images of the latest Bryston models. If they still have the same binding post then the binding post is current and will be available from suppliers. James and the Russel bros, aren't going to hobble themselves by using obsolete parts on current items being manufactured. They are too wise for that.