Hi Raul,
I believe the dealer in El Cajon is this one: RV Rentals, Sales, Service, Camper Trailer Outlet
They do advertising on RVTrader.com This is probably the same former Hi-Lo dealer Les mentions so it looks like they are still selling used ones. Anyone on the west coast looking for a Hi-Lo may want to consider giving them a visit!
You are correct that there is no stereo in the unit. I'll take a look in the locations you mention to see if I can locate the wiring. How would you run the speaker wiring from above the kitchen counter to the wall above the dinette?
Thanks,
The wires to the speakers should already be there.