Interesting Irine... I thought lobster was a lot more affordable in Negril, especially for Americans since the Jamaican dollar has devalued in the last few years comparatively.
3 Dives and Kool Vybes is approx 3000j (approx. $23us) for 1 ½ lobsters...much cheaper than previous years.

Check out the link below...there's a shop in the West End that sells seafood...
http://negril.com/nt/nt032516.htm