Stamped English pewter tankard: Legit?

[Bradley]

Found this in one of my picks. Haven't bought it yet. Sales tag claims it is "1700s English Pewter" and I am wondering if that is true. Bad new is that I do not know my English pewter stamps. Good news is there are a few here, which might provide good info for those stamp aficionados.

Even if the sales tag is accurate, I am not terribly interested in purchasing pewter with a high lead content, and I would have to test this item first.

[mart]

http://www.pewtersociety.org/identify/verification-and-capacity-marks

According to the above and as I read it,, the possibility is that it would be prior to 1836 !!  But as stated above that is no guarantee because the rules were not always followed till years later !!