I do my own processing for Super8 BW and labs for 16mm. All a question of taste. I like BW, but prefer in 16 mm. As for cameras, I have several Nizo, Beaulieu and a Leicina as well as the little Canon 310. Another quality camera was made by Bauer. Much of the choice depends upon how comfortable the camera feels in your hands. That was the reason for my choices. Yours could be different. The key reason for choosing a Super8 camera is stability of the gate. Leicina wins hands down, followed closely by my other two choices. Nikon, Canon, and Bauer are also known for image stability.
Because comfort in hands is so important, I would buy from reputable dealer with unconditional return policy. A good place to start would be DuAll camera in NYC. Primarily a rental and repair house, they are quite knowledgeable about Super8 cameras and usually have some available for sale. They are also generous with info.