Some RFAs that I sailed in used sprung Volvo truck seats. Some of the earlier ships (early "Tide" class comes to mind) had passenger seats from old aircraft mounten on a wooden box thing. "Rexon" covered, horrible things.
It is quite common for car manufacturers to donate "something" to a ship. Two that come to mind was the Scimitar weapon presented to HMS "Scimitar" by the Reliant manufacturers and the huge (about 3ft dia) Jaguar badge presented to HMS "Jaguar"..that instead of (say) 3.5 Litre on it, it read something like 50,000 litre! No doubt there were others. BY.