From the Flyers I'd take Voracek in return. So a big, big time overpayment. Basically only way I'd move him to Flyers is assuming he's reaches his maximum potential there and require payment based on that.
From any other team, I would listen to reasonable offers.
Can't see the Pens dealing him directly to the Flyers unless it's overpayment and the Flyers won't do that. The only way he winds up on the Flyers anytime soon is if another team acquires him in a deal with the Pens and then flips him to the Flyers in a separate deal.
Tangradi hasn't done anything to make him a valuable trade piece.
Instead, the fact that he hasn't done anything should be used to sign him for cheap, as long term as possible, and then have him contribute to our team.
We have a star heavy team. It needs cheap complimentary players. Play Tangradi and let him develop to what he he should become. Even if he'd never become more than a Taylor Pyatt, that would be useful on this size-challenged team.