I think the TU-717 will be running closer to $300(or more occasinally) at least on ebay. I watched them recently for a couple months before I picked something up. The TU-9900 might well run up to, or over, $500 in stock form, depending on condition(again, ebay). The TU-919 is a real gem, but the prices are pretty rightous in the $700-$900 range, stock. One went recently for $800+.
The down side of picking up one of the better models(read: higher priced though in your price range) is that it'll be in stock condition & probably not checked out & aligned in a very long time. If you're looking to save a couple dollars it may be a better tack to pick up something that is technically very good (# gangs..etc.., see FM Tuner site) even if it is a "lesser" tuner and then have some work done on it. The resulting unit will then either equal or exceed the higher end (stock condition) tuner-examples in performance. Actually I read a post here on A-gon by a very well known writer-technician in audio-dom that a TU-317(?) & TU-417(?) that he modified turned out to be some of the better performing tuners he'd ever seen.
One last thought...you might contact someone who does mods and ask them what they think is the best bang for the buck in a modified, low priced tuner.
