Seat belt bolts

[TOMTOM]

Hello, pulled my interior from the loft to clean it all, anyways, the rear seat belt bolts, I've managed to lose them!! Would it be a bright idea to go to a fixings firm and get some to the required lengths, and fit the belts etc and use a bit of lock thread to help em secure a touch more? Or should I really be using the genuine jobbies? I want it to be safe but what's the general thinking? Thanks in advance if anyone can help :)

[Bigfoot]

I should have a load of the bolts somewhere up in the loft plus the metal spacer bits if need be. More than welcome to come over and take a look if you want