I mentioned earlier in the Derrek Lee Arbitration thread that Hanrahan's trade value would soon be identified, probably by a trade involving Andrew Bailey.
Here is Molina's write up. (Fangraphs page)
2) Nestor Molina, RHP, Grade B+: Ranking the Blue Jays pitching prospects is quite difficult. Although Molina hasn't received as much press as some of the other guys, his performance was impeccable, I think his stuff is underrated, and he'll get to the majors sooner than the others. Despite his season, he is still underrated by a lot of people.
Santos (Fangraphs Page) is 28, put up a FIP of 2.87 and a xFIP of 2.69 last year and 30 saves, and is signed to a very good deal worth 8.25 million over the next three years. In addition, the Blue Jays will have three club options, but they are much more expensive, at 6 million in 2015, 8 million in 2016, and 8.75 million in 2017, with a .75 M buyout.
Hanrahan (Fangraphs Page) is 30, put up a FIP of 2.18 and a xFIP of 2.98 last year, with 37 saves, and is controlled for 3 more years, all arbitration years, so he has less team control and is somewhat more expensive in the short term.
I'd argue Santos has a bit more of trade value than Hanrahan, even though the Hammer has an all-star game to hang his hat on. Still, it wouldn't be crazy to imagine Hanrahan getting a similar return to Molina.
According to Sickels's grade of Molina, and projecting how Sickels will grade the Pirates, if we had acquired Molina I'd think he'd slot in the 3rd to 5th spot in John's rankings. I would probably put him in that same range.
Ultimately, I think if Hanrahan can bring back a similar haul at this point, the Pirates should trade Hanrahan, although the lack of any trade rumors surrounding the Hammer indicates that it probably will not happen.