If the pad-holding slot on your brake calipers is long enough, you can adjust the pads to fit a 700c rim, so no new calipers needed. Just pop any 700c wheel in the frame and see if the pads will adjust to that rim. If you have downtube friction shifters, you can run any of several freewheel gear ranges.
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1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"