Agree with the suggestions to check Super U in Hope Estate. They usually have a good selection of Leffe products. And of course you can get Kronenbourg 1664 there (a French beer). The other thing if you haven't tried is Desperados. It's more of a beer-based beverage than beer, as it contains other stuff like flavorings and sweeteners but it's sometimes a nice change of pace.
I've never been, but FWI Bar & Brewery is basically next door to the Super U and they make some local craft beers. I don't know if you can carryout beer from there, or if it is more of a brewpub / restaurant. Might be worth checking though.
.
