Hi, the KM# 47a from Mexico does not have the option to select a non-dated coin, these coins are very irregular and some coins don't have the date on them. The link is this:
https://en.numista.com/catalogue/pieces28663.html
and also you have the picture of the KM# 47 wrong, the picture that is there corresponds to the KM# R47 which are circular well defined coins; the KM# 47 is irregular and not always has a date, other than that the dates are OK.
The link for the KM# 47 with the wrong pic is this:
https://en.numista.com/catalogue/pieces15058.html
Please check this, if you want I can upload the coins that are missing so the Mexican catalog can be complete.
Thanks.