This has been a very quiet offseason for both the Pirates and Morales. Pittsburgh has signed Edinson Volquez as a free agent and Charlie Morton to an extension, but otherwise almost all of their moves have been minor trades and signings. Morales, who is attached to draft pick compensation, has not drawn much interest at all.
Last summer, Pirates' first basemen hit .264/.346/.422 with 17 homers, nearly identical to the .261/.337/.436 batting line put up by the average MLB first baseman. Gaby Sanchez crushed left-handers (.333/.438/.539), so adding a platoon partner will suffice. They don't necessarily need to add a full-time player at the position.
Morales, 30, hit .277/.336/.449 (123 OPS+) with 23 home runs in 156 games for the Mariners last year. He has played only 59 games at first base (214 at DH) over the last two years, so it's fair to wonder if he can even play the field full-time. The switch-hitting Morales doesn't have much of a platoon split, so pairing him Sanchez doesn't make much sense.
The Pirates currently own the 25th overall pick in this summer's draft after winning 94 games last season. They are widely considered to have one of the very best farm systems in baseball, so sacrificing a top pick to improve the big league team shouldn't be off the table. I'm not sure if Morales is the guy worth surrendering that 25th pick for, however.