It might not be your oven termostat. The problem might be that your oven needs to be calibrated. It is a rather lengthy and involved process, but any RV Tech worth their salt should be able to do it for you. You can also do this if you have the proper manual.
If the oven is out of calibration, a new t/stat will not solve the problem. Chack on the oven manufacturer's web site for your model and see if they list the procedure in the operations or service manual.
Lew Farber...RVIA Certified Master Tech...ABYC Certified Master Marine Electrician
SOLAR TECH ENERGY SYSTEMS, INC.
AM SOLAR ...MAGNUM…VICTRON ENERGY...LITHIUM & LIFELINE BATTERIES…MARINE REFRIGERATION