Never noticed this before but check out the exhaust can on the regulator in this famous photo.
The main label appears to be gold or brass as does the curved label above it...... We have all seen plenty of Stream Air's (red, tab) and Overpressure breathing (yellow, rivet) regulators with the curved Mistral sticker about them but none that look like this one. Perhaps someone has a better copy that can be more easily read?
I stole this from Ryan's FB feed today.