Santeria and Catholicism?

I was raised Catholic all my life but as of now, I'm a non-practicing Christian. My partner is a member of Santeria and as time as been going on, he has taught me and introduced me to this religion. I'm enjoying it from a distance because I'm still a little nervous about changing religions. Anyways, in his room he has statues of each "Orisha" except one, Oy� (Saint Theresa). I offered to buy one for him to complete his collection. If I purchase a statue of Saint Theresa from a Christian store to be used in Santeria, is this wrong? Or should I just go to a botanica and buy the original Yoruban style statue? Oh, he said it would be better if I got it from where I usually pray... which wouldn't be from the botanica but from a church? Thanks!