Hello Beebe welcome to the forums. not a bad looking bike but clearly (to me atleast) a mid '90s. the Meche crankset as well as front hub are stock. the bike appears to a '95 with a mix of shimano 300/400EX parts. the tall stem makes me nervous, either the seller is small with a real bad back or to tall for the bike.
I wish I could see a better pic of the otherside of the bike but I kind of agree that derailleur is likely not broken but just needs adjusted or a cable. (the derailluer is not visiably hanging of the frame and the chain does not look slack so I do not think it is broke)
I think 175 might be a good deal for this but never hurts to try and haggle a bit. I would get rid of that stema dn get a tune up and you should be all set.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk