Get the motor and you should be able to find information stamped into the metal. Do a general search and see if you get any hits. A good source for motors is a company called Whitehouse Products in the UK, but don't let that scare you, it will be cheaper even with Fx and shipping. https://www.whitehouseproductsltd.com/home
My coach is 2002 model and the have a replacement for it. I bought a new thermovalve from them in 2015, saved a bunch of money. https://www.whitehouseproductsltd.com/home
If no luck there take the motor to a good hydraulic shop, they deal with rebuilding or replacing these types of motors. Unless the gears are damaged or shaft broken chances are it is rebuildable with new seals and bearings.