Not that I see us doing this any time soon, but if we ever decide we need to arm our H-60s against smaller targets such as fast inshore attack craft, it looks like it might not be too difficult.
The APKWS guided 70 mm rockets and Hellfire systems that are included in the program,appear appropriate for countering small vessels.
Photo: Technicians install the Arnold Defense LWL-12 lightweight 2.75-inch (70mm) rocket launcher.
Chuck Hill's CG Blog 
A good idea, especially since the USN doesn’t have enough gunshhips per se. Their SeaHawks are planned as convertible which means ship attack weapons may NOT be on them when needed~
Maybe, but not because of what is said in this article. The H-60J/T is part of the Seahawk line. While based on the mechanicals of the black hawk, they use a much different airframe than the Black Hawks are are not compatible with the External Stores Support System (ESSS). However, The Jayhawk, like other members of the Seahawk line has 3 integrated pylons. 2 fuselage “torpedo” hard points and a port side wing pylon for other ordnance. (The new MH-60R also adds a 4th, a support pylon for missiles/ rockets between the sliding door and the starboard pilot’s door.) The Coast Guard exclusively uses these 3 pylons for external fuel tanks to extend the Jayhawk’s range. Its not impossible though, that the port wing pylon is either capable or could be modified for weapons if the need arises.
That said, if the Coast Guard were to move to the MH-60S to replace its aging H-60s and H-65s, they are based on the Black Hawk airframe (with the Sea Hawk’s marinised/ folding parts thrown in) and are compatible with the Army’s 2 and 4 pylon ESSS system fro this article.