I have a genuine Patek Philippe strap I purchased from my local Patek AD and have only worn 10 - 12 times.
It is for watches 18mm at the lugs and can be found for sale here:
http://www.rwg.cc/members/index.php?showtopic=12184
I think I am allergic to nickel but only when it is warm and my wrist sweats.
Search for some threads from this summer, this came up a couple of times.
Modern gen 904L Rolex steel contains almost twice the nickel of 316L.
So we're using the razor blade to etch deeper into the small tin part that folds over the clasp to secure it into place?
Take the razor blade and scratch deeper along the two lines across it?
Nanuq has probably already done this but with a chainsaw.