The mk3's were done as standard weren't they? Every one I've seen has (or has the remains of) white infilling in the lettering.
I'm not as certain with BSA's but definitely had a few old ones with white lettering (whether it was original or not I don't know).
The 80's Webley's is what I've seen the gold used on; Osprey, Tracker, Vulcan etc.
Cheers
Greg