Atm not really any conversion tools. My table has been reskinning items to make them fit, though. Guns exist in my game, and I just use crossbows to simulate them, and recommend ranger as a good candidate for refluffing to get the gunslinger feel. Crossbow ace is a given, cowboy types can take an animal companion, etc
Occult classes really dont have an analog, but refluffing the bard or aberrant sorcerer may be a respectable start. Similarly, clerics make just as good cultists as they do healers.