The good news (I guess) is that Sears really did sell 531 DB bikes for a while. I just acquired one that had been posted, in modified form, on E-Bay some weeks ago. It is interesting:
Still has the Reynolds stickers, much worn, nice 1/2 chrome fork with chrome crown (oval blades, not round like the earlier Ted Williams). Nice lime green finish with black striping on simple lugs that weren't thinned at all. Shimano drops fore and aft. And it came with the Original Sears Lightweight Owners Manual, dated 1973, printed in Austria, with nice illustrations of the SR maxi-style cranks, stem shifters, and suicide brake levers (UGH). All the "spoor" I'm used to seeing on Austro-Daimler/Puch/Steyr bikes. (I think, but am not sure, that Steyr was part of the same group). At the seat tube to top tube junction, there is the same sort of 1 cm tall trapezoidal punch-out of the seat tube instead of a hole for gas relief (?) while brazing up. Same cylindrical brake bolt seat on the seat stay/brake bridge. Has the proper Shimano Crane and Tourney derailleurs.
So the bad news you want, too? One starts with the classic sheet metal chainstay bridge that accomodates the ESGE kick stand. I guess it reflects well on the prior owner that he seems to have carefully removed all the funky old Sears decals and the glue-on headbadge. So riding it doesn't give near enough anti-Mojo points, because even the cognoscenti can't tell its lowly birth.
The components have been largely upgraded or at least replaced, except for the hideous cranks. I imagine it will eventually become an organ donor, but not until I put together enough to ride once. I just can't imagine spending the time to do enough bottom-feeding to find the right Shimano stemshifters and brake levers. :-(. Offers of same not really sought...
Harvey "bottom feeders unanimous" Sachs mcLean va