That is the same shaft as a lot of other Singers use like the later model 221, 185J/K, 301, 328K, 401, 500A and so forth.The only trick is the type of nut and tensioner that was on it. If you like the ones with the numbers then use a slant shank type and use the entire assembly. It is an easy piece to find and I probably have a few out in the studio. PM me and I will see what I have.
Billy