I heard Huntington on the flagship radio station with Rocco tonight, and there was some talk about opening the season with 11 pitchers. If the Bucs would do that, they could carry 6 reserve position players. They would begin the season with 11 pitchers until Hanrahan returns around the 15th of April. This may give them a little extra time to make a deal for Vasquez, or even Moss. If one of them was traded prior to April 5th, they could get a longer look at Raynor.
Assuming that the Pirates DL Hanrahan and backdate 10 days like they have talked about...he could return April 10th. Considering that today was Dotel's 1st Grapefruit League appearance and they say he will be ready for Opening Day, the same thing may be possible with Hanrahan...since he is throwing. I'm sure that one of the roster spots (a pitcher) will become apparent this weekend. They can put Ascanio on the 60 day DL as early as tomorrow (it may be Friday, as I don't know if it's MLB Opening Day or the Pirates Opening Day that they are able to backdate from). That opens up a spot on the 40 man roster where they can add one of the NRI's (Carrasco, Chulk, Taschner, etc) if they are going to add one to the bullpen, which appears likely.
I'd think a deal for Vazquez or Moss, if it happens, would occur before Opening Day, as teams are ready to file their 25 man rosters. Short of a major injury the first week of the season...there's no advantage to waiting a week into the season. Otherwise, teams will just wait for the roster crunch, knowing that they could be picked up on waivers.