And this is increasingly the problem...
Whilst somewhere there will no doubt be a few genuine high grade die number 64's, as has been said above the VAST MAJORITY of these are modern, high quality white metal pressure cast fakes originating in the Far East. The cud on the N of tenth is a good pointer to these as well as the attendant fine circumferential die crack that connects many of the letters of the reverse legend - maybe a fault in the original pressure mould or on the original host coin, but now replicated manifold.
Unless you can do a metal test or a conductivity test (such as with one of today's sophisticated metal detectors), I would be VERY wary of purchasing a die 64 1864 florin!
Beware also of course "nice" 1905 halfcrowns, wreath crowns, 1850 shillings and so on. All have their diagnostic flaws some easier to spot than others - eg. wrong font 5 and 0 (too large and bulbous) on the shillings, dodgy QVI in the garter of the halfcrowns etc.
Other fakes that aren't taken from a host coin, such as the quarter farthings mentioned above and the plethora of replica 1933 pennies, but which are made with modern CAD created dies are easier to spot as they just aren't accurate enough, but still fool many collectors, both novice and more experienced. Beware!