There is no limit on cigars or rum any more (since October 2016, and unchanged today; according to those who have discussed it, even after the forthcoming resumption of sanctions against People to People trips to Cuba, there will still be no additional restriction on cigars and rum).

The rule is: no limits, but you get 100 cigars (or $1000 worth, if you reach that before 100 cigars) *duty free* and the duty after that is around 4% -- so essentially nothing, and that's if they even ask you. All I got was a quick "Did you bring back cigars? (yes) Did you bring back more than 100? (no)" and that was it. They never looked. Of course, that was prior to the June Trump announcement.

These rules apply whether bringing Cuba products directly from Cuba, or from a 3rd party country such as France or Mexico.