Eley Bros percussion caps for Colts pistols

I’m aware that percussion cap tins labelled for the Colt pistols were reproduced at some time, and probably still are. This label appears legitimate, and is on a Japanned finish tin, so I’m fairly confident it is correct. Does anyone here have any tips for determining if one of these tins is correct?

image

Just the usual not a Xerox tests & period printing methods being correct.

These are being Xeroxed / faked also.