Aren't there some black hotstamped chips with E.L.P. on them? I can't remember the mold, but I'm thinking I have one. Will have to check at home to see where I have it listed as being from.

While googling I came across an article on Cuban chips in a Cuban Numismatic Association newsletter that might give you a lead. I noticed it mentions that the Tropicana offered a native Cuban game called "Monte y Dados". I wonder if that's what the MD on your chips stands for. Here's the link, it's a PDF file:

http://tinyurl.com/p88zq