I wouldn't be surprised if many bike people do "collect" bikes from time to time. Unless, of course, there was something particularly unique about your cranks.

There may be some companies that are making repro cranks from scratch, and the cranksets from the 60's and 70's would make excellent patterns as they would make good designs for cutting billet cranks on a CNC. 180+mm cranks? Shorter than 165 cranks?