Personally, I would cut off the Marinco plug and install a standard 30A[at]120VAC plug. The RV world generally uses the standard straight plugs and sockets, plus the Marino stuf is expensive because it is marketed to the commercial and marine areas.
Be SURE that all your stuf is for 120VAC, NOT 240VAC, because if you did wind up making a 240VAC connection, you will let the smoke out of your converter, fridge
control board, lights
In the RV world, the ONLY 240VAC connection is the 50Amp at park pedestal, which is changed to two 50A[at]120VAC circuits in BulgeMobile wiring (So they can run both a/c at the same time).