But that catalog photo ^ shows under-the-chainstay cable routing, and in the craigslist photo I'm pretty sure I see the little bell cable stop on top of the chainstay.

I believe this likely puts it as earlier than '83.

It looks quite a bit like my '81 710, but mine has rear rack mounts on the seatstays, and the chainstay cable stop on mine is also a different shape.

My guess based on all this and the observations above was going to be '82 730 or 736. But the catalog photos seem to show under-the-chainstay routing for those models -- and above-the-chainstay routing for the more "touring" oriented models! A transitional year, I guess.

Whatever it is, if it is cheap, and I were in your shoes, I'd snatch it up.

Here's mine: