That's the thing, even if he is apparently the best winger available in the market, teams still aren't going to overpay just for the sole reason that he is one of the few options available in the market. Any sensible GM wouldn't overpay just for the rarity of a player, if he does, he really shouldn't be working in the NHL.
Hell, if Glencross is wanted by a bunch of NHL teams, wouldn't they have a pretty darn good idea of how he has been and how he will be? His strengths are clear: size up front, good in front of the goalies, good at deflecting pucks, and can score. His weaknesses however have been more evident than his strengths: not enough jump to his game, gives pucks away easily, has trouble making plays, and looks demoralized with the puck.
Teams are going to only pay within the boundaries of his true value, and those boundaries honestly should not be any higher than a 2nd + B-level prospect. If that's what we get, Treliving deserves a victory cigar. Anything better than 3rd + B-level prospect is a success.