Once again, I don't believe there's currently a reliable veteran offensive lineman available interested in joining the Packers to sit on the bench. The most likely scenario to improve the depth would be to take a gamble on an ascending young player capable of playing multiple positions in my opinion.
I get that, but do you seriously believe that one of "those" guys, that as the OP suggested, who is currently sitting on another teams PS, is actually going to step right in this year and help what appears to be a lack of depth?
IMO, the most likely scenario to immediately improve our depth on the OL is to sign someone with NFL experience to back up some of the starters. I will take your word for it that currently THAT player doesn't exist on the FA market, but that also shouldn't rule out TT looking around to swing a trade for that player either.
I hope I am wrong and we may find out as quick as this Sunday if Bulaga can't go, but I think we are in a bit of trouble when one of the current 5 starting OL can't play and god forbid, 2 of them go down.
I don't doubt that when things slow down a bit, TT will be actively looking at other teams PS and FA's to see if he can improve his own depth for the near future, I'm more concerned about the immediate future.