Initially I thought it might be a early 1990s set out of Puerto Rico, maybe an oddball BYN set, but it turns out that it is from 2012 or latter. Looks like most are older/HOF players but they also have Jim Thome and Ivan Rodriguez with stats through their 2011-12 season in Puerto Rico.
Considering that there is no team logo, league logo, manufacturer name/logo or even a copyright leads me to believe this is a Broder set. Someone put together a set of players who played in PR and printed them out. On the Frank Howard card they even used a cutout of one of the Topps cartoons from the back of one of his Topps cards. This set is purely custom.