Those are very nice half busts. What is interesting about these coins is that the variety experts know all the dies and the die states. Do you know the attribution of your 1920. My only example is this one, and I think it has been tooled Ruben
That's a great looking 8 reales, the attibution from Gilboy is M-8-40. And Manila Gallery is a safe choice IMO, considering the large number of fakes being sold on ebay.
Thanks for the attribution, Acanthite. You can bet I studied it very carefully when it arrived!(I've had good luck with Manila Gallery, though, nice people who know their coins) Here is another bust half, an 1829
Here are a couple of crusty busties, I really like these, especially the half with that "circam" look.