I have an older Murray panel that I would like to add a circuit to. The panel says to use Type MP breakers, but I could only find Type MP-T breakers at Home Depot or the supply house. Will the Type MP-T work? FWIW, the panel currently has another brand breaker in it, I believe a GE.

I have some basic electrical knowledge having renovated multiple homes and doing some of the basics myself while leaving the major work to professionals - like increasing from 200a to 400a with new panels, etc. In this instance I think I can handle this but want to make sure what is needed. A home inspector noted in his report that "The breaker panels were not bonded to the grounding buses. Should a short circuit occur, the breaker panels would become energized rather than sending the short circuit to ground." What is needed here? Is this a heavy copper wire from ground bus to a screw on the back of the metal box? Please reply with all necessary details if you have pointers here. This is a 200A main service with a 100A sub panel directly next to it. Westinghouse / Bryant panels. thanks!