They should be fine on your 50R. I prefer a mixed set of hard-tension Cantigas with normal-tension Alliance on almost all of my guitars. That would be Cantiga 540ARJ.
You might want to start with 510AR (normal tension for all strings) first to see how your Cordoba responds and if you like the feel. If you want a little more power to the basses, then go for the 540ARJ.
"The hardest time for most guitar players is the beginning stage, because it is all investment and no return." - Charlotte Adams
"It's not your guitar or lute that matters but what you can do with it." - Moi