Unfortunately, Ken may not be off by much if the cue is to be sold in a general auction. Even if he underestimated by a factor of 2, $200 would still be pretty small money for a cue with this high quality. I played all this weekend with my 1985 Joss merry widow. It's a fine cue that is still straight after 28 years. I keep watch on similar cues and they don't seem to grab what they're worth IMO.
The OP might consider doing what I did - keep it. There are always places and situations where I do not want to take a much more expensive cue. It is a real luxury to have a great playing back up cue that does not present a substantial financial risk.
No matter what the owner decides, I would clean up the ferrules. Mine are ivory and still look new. The butt also provides a great base for an LD shaft.