I didn't blueprint this part, but I do have good reference for the original and could blueprint it.
If someone has the MR and can check the overall diameter that would be useful.
There are two problems with doing this part.
1. The knurling on the angled surface. I don't know if Russ, Rylo or whoever would have the necessary tooling to do that.
2. The center hole. Since this would be to replace an existing nut on everyone's blasters it would need to have the same threading. Either that or replace the bolt on the blasters as well, which could be difficult to do - mine is threaded into the Mauser body itself.
I think Corellian Exports, BlastTech and Bobadebt have all done these ESB mounting brackets. What is the threading for each?
If they are all the same then it would be easy.