Info Needed.1969 San Diego 200th Anniversary Medal (Id: Replica Silver Round, Perhaps From Mexico)

Obverse looks like a knock-off of this Congressional Comm Medal (which was struck by the USM and sold at banks in SD County)

https://en.numista.com/catalogue/ex...a180237.html

Reverses are dissimilar.

Here's a current listing for the USM version
https://www.ebay.com/itm/1654987276...9v3PT6hknvPc

Here's a listing for a version that matches the OP's:
https://chulavistacoins.com/product...anacs-au-53/

Design element descriptions in the second link are inaccurate, e.g., no covered wagon.
The "Pura Plata" on the reverse would seem to indicate the coin was struck in Mexico

Good luck with your detective work.

Here is the text from that chulasvistacoins website for when the link becomes broken: