I know I'm a little bit late in answering this, but I have 2 Singer 99's, a 1924 99 with a foot petal and a 1928 one with the knee bar. They both have the lovely bentwood cases. I paid $75 and $50 for mine. Neither one came with an instruction book, which you can download from the net., and all of my short shank attachments for my other machines will work with them. They are quiet but heavy little machines and I wouldn't trade either of them for anything else. They were both made in the US.
So, if you can get one in trade for the loan that you gave and never expected to receive back, you are getting a good deal, in my opinion.