I would not go over $75 for one with missing parts. You may find the missing stuff eventually, but you can't just skip down to Wal-Mart for those things.
I guess you have already seen this article, since that's where the photo came from.
http://antiqueradio.org/motvt73.htm
These Motorolas are just about the most common vintage TV model, along with Philco Predictas. Don't pay too much for one, or you may regret it later. It's an unusual week when you don't see at least a couple of these on eBay.
Phil Nelson