They are not two faiths--the name "santeria" was a perjorative one imposed by the Spanish. "Regla de ocha/Lucumi/Ocha" are the names actually used by practioners. Certainly, there are different styles of worship--some never use the Yoruba names of the Orisha, and prefer to front like they're Catholic, while others are full-on Ifa practicioners with little use for the Catholic trappings. I would say the latter is "serious" Orisha veneration, while the former is pretty much empty ritual.
I'm sure that Ifa/Regla de Ocha was being practiced on Puerto Rico (and consequently here on the mainland) before the 1950s. Everything I know about the issue pinpoints the mass migration after the revolution as the starting point for mainland growth. Yoruba (who are properly called Anago, but that's a whole other thread) spirituality was being practiced here in the South, like South Carolina, Georgia and the Sea Islands as well.