Tom, have you had any luck with RC on getting either a key or nos switch?
When I got my Bridgestones 3 years ago, one of the first pieces I inquired about was the ign. switch and at that time was told he had none. Has he gotten some more in?
On a side note, both my GTO's had original switches and both had "700" numbered keys. I recently got my hands on some nos switches and they're all "100" numbered. (102, 103 &104) Based on what I'm seeing, I believe your original switch had been replaced at some point with an off the shelf nos piece.