If you're trying to stay somewhat vintage and go with a 5-7 speed-

check out the suntour stuff,
it was technically the best for that era.
probably the cyclone but if you want to go newer the suntour superbe stuff works great.

from there i'd go to the campy nuovo record or super record, depends if you like the cast or smooth look.

I've got a shimano 600 (arabesque style) rear derailleur,
used but worked fine shipped from san diego for $25.

TP

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