http://www.whatifsports.com/HBD/Pages/Popups/PlayerProfile.aspx?pid=5646638

http://www.whatifsports.com/HBD/Pages/Popups/PlayerProfile.aspx?pid=4445342

http://www.whatifsports.com/HBD/Pages/Popups/PlayerProfile.aspx?pid=7145726

All are being offered in reasonable trades? Who would you like best for DH role?

Gorkys Olmedo

Oliver Theriot

Oswaldo Mercado

Olmedo or Mercado. I'm partial to Power so would go with Olmedo, but Mercado has the advantage of being able to play 1B in a pinch. Would have less interest in a 36-yo DH given a reasonable similarity to 26yo and 20yo.

Theriot is the best of the 3 right now, as he hits RHP much better than the other two-- but he might decline within the season and Mercado will likely improve some.  I'd go with Mercado.  

Mercado. He looks like he'll become a competent 1B, whereas the others are just DHs. And I assume he'll improve as a hitter, since this is his second full season. Dedelman is right that Theriot is a decent hitter, but he has 45 durability, so I don't see him playing more than 80 games. If you just need a pinch hitter, take him. Olmedo has good power, but I'm afraid of that 41 eye. He'll be very inconsistent, and he'll struggle with low OBL, which isn't something you want from a DH.