found these recently, photo is not the best.   Starrett 245 (apparently they still make it) and a Bruno adjustable drill bit (apparently they're gone (but stamped as Beverly Hills on the bit).    On the Starrett, the one gauge is marked "Birmingham standard" and the other sticking out is a taper thickness gauge.  There are several tapered width thickness gauges from from .002 up to one marked 1/16.   Yeah, i don't get it, either.  Hoping to find a good way to clean the rust off those really thin "blades". 

Cool find Pete.  I have never used evaporust which has gotten good reviews and recommendations on this site.  I have done electrolysis though, and I believe it would do an excellent job on this task for you.

Honestly, I have a gallon of Evaporust in the garage and have used it on various saw blades (with another saw waiting in the wings to lose its handle and get dipped).   What i'm not sure is how easy it would be to clean that off the too thicker parts, never mind the very thing gage material.   The electrolysis might work better if i take this apart (screw holding the end looks like it will come out), but again...some very thing blades in there.

You could also try apple cider vinegar. Do not leave in over 2-3 hours without checking on it as it will pit metal. For this application probably 45 to 60 minutes will do. Wire brush and rinse thoroughly.