I have just had a good tidy up, and found this bronze leadscrew nut, which is brand new but scruffy. It is .875" O/D and 1 1/4" long, with a good chamfer on 1 end. It is LH and about 1/2" acme or square thread. I have reason to think it could be a nut for a Harrison L5 tailstock barrel, I had an L5 a long while back. Can anyone identify it please?