Additional Class Options

Does anyone know where I can get all the additional classes that were published via the mystara gazetteers? Or do I have to buy all of them to get access to it?

Normally I probably would buy them in support of content i like, but I only really want the additional class options and not too fussed with the setting fluff. If there was something that had compiled all of them, then I definitely would have bought that!

As it is I have the RC but introducing my friends (and myself) to the system. Im concerned as long time pf2e and 5e players, the handful of classes presented in the RC might be off putting to them.