If you're a certified cave diver and looking for sidemount instruction, I would highly recommend contacting Nat at Under the Jungle. She's one of the best, most dedicated dive instructors I've ever met, and she has teaching SM down to a real science. If you took her class, you'd have to suffer through a vacation on the Mayan Riviera, so that might not interest you, lol. But you should still contact her, she knows tons of great divers and teachers, some in the U.S.
But here's a weird question, if you have taken cavern and cave classes, and you're interested in sidemount, why would you be only interested in OW? The whole reason I learned SM was to facilitate easier diving in the Mexico caves. For OW what's wrong with BM doubles, if you even need doubles?
If you do go to UTJ for a SM class, be warned, once you get going in those Mexican caves they can become VERY addictive.
View attachment 781691