peugeot partner 2004 - universal seat belts - srjsrj

hello

the middle rear seat belt in my peugeot partner has had the strap cut (before i bought it) - can i get a universal car seat belt instead - do I need to look for anything in particular - or are they truly universal?? (we don't even use the seat - would take it out if we could but it is the double one )

any advice greatly appreciated