It seems the unit in out trailer is a low wattage unit compared to anything on the market that I can see. Here is a link that may stick around for a bit.
I believe the system is rated at 6 Ohms so its good to stick as close to that as possible. Most mini-home systems are 3 or 4 Ohms and Standard Home Amp systems with big old speakers tend to be 8 Ohms.
My suggest would be to find a decent unit in the 4 Ohm range preferably under 400 Watts to avoid popping the speakers.
If I have any more info, I will post it up. I still have not found a good replacement yet but am just starting my search.