Looks like a 'pistole' or two escudos of Seville, Spain under King Philip III, circa1617 - 1621. If so, it would have Assayer letter 'G' off flan to the left of the shield.. it looks real from the photos. This is a nice find.
I am definately not an expert on these whatsoever but had to chime in on such a beautiful "coin". I would lean towards authentic myself if its 22k as you say. The surfaces and cuts all look good. Weight is fairly spot on according to the practical book of Cobs weight should be approximately 6.75g. Heres a link to the website of a specialist he may be able to help if someone on here cant.