Working in a re-sale shop as I do we get a lot of furniture in (And out).
The Sofa in my RV is, save for fabric, Identical to the one my parents had, it is identical to many we have run through the store..
You ask "What about seat belts"
They are not part of the sofa, they are bolted to the floor UNDER the sofa (to the frame actually) you simply reach down and pull them up through the cushions where the seat meets the back.
But the sofa I'm sitting on as I type this.. is a standard residential jackknife convertible sofa/bed. You may replace as you sish. however chairs should not be used for seating while in motion unless they are the proper type. And properly bolted in place.
In many Rv's the sofa is not even bolted in.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times