These gold "minatures" were mass-produced in Mexico back in the 1960s to the 1980s. There were numerous manufacturers, of varying artistic effort. They are usually made of solid gold, though 8 or 14 karat is normal. They were originally intended as jewellery pieces, though they found that selling them as-is to tourists worked just as well. I remember a local mail-order coin dealer here in Australia selling them for $8 each, back when gold spiked at $600/ounce in the early 1980s.
They replicated the designs of not just Mexican and American gold coins, but common gold coins of other countries too. The mail-order advert I rcall had six or eight different designs on offer. The American ones, of course, were more popular (and thus are more commonly found) in America. So yes, a "cheap way to own a gold coin" - even though it's not a genuine gold coin.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis