Jacques,

I can recommend Quickfit.

I had a new set of inertia reel seatbelts made by them, with a 5" drop link on the B pillar, in a shade of blue to match the plaid in my seats. The link is to stop the belt cutting across my neck, which I never liked with the originals. I also had to make some new floor bolts in stainless steel to suit the new buckles, since the ones that Ferrari used are no longer available.

Neil.