I think you're going to find that you'll need to figure this out for yourself.
See, Winnebago custom makes all their TV mounts. It's not really anything just out there to order. But, TV's use the same kind of mounts for all kinds of walls. They are standardized by bolt hole sizes and spreads on the back of the TV. The standard is called a VESA TV Mount.
So, if you look at various TV mounts on Amazon, Best Buy, and probably Home Depot, Lowes, Target and Walmart you'll find the one that fits your new TV and then you'll need to figure out which of them will let you mount the mount to your wall. This is totally something you'll need to figure out.
Here's a kind of standard, inexpensive mount that can fit a lot of installation options. NOTE: the mount you get will also be dependent on the TV you buy and it's weight.
https://www.amazon.com/Mount-Compute.../dp/B00KZP1BUI
I
'm not saying this is what you need to buy - I'm saying that something like this that fits the TV you buy, the weight of the TV you buy, and looks like it will attach to your RV's wall.