Did Fantasy Flight ever provide an alternative to buying 3 copies of the game to own a full playset of each of the Core Set Players' Cards? Am just curious. Can't find anything on this anywhere.

Nope. Many players have purchased at least two Core sets. But for three of each card, you will have to buy three Core sets.

Some companies sell individual cards online - 3x of the 13 cards that are only 1x will cost you nearly as much as a core set anyway. On the other hand, if you just want 1 or 2 - a third unexpected courage or similar, then it might be worth investigating