..Cuban.
The "1955-56, a total of 3 orders," came from the Burt Co records. Burt shipped them to Mason so they would have no final destination for the order.

They are on the new hub mold, (smaller at the bottom than the top).
I just recieved this comment from my source.
"Gene
I would agree that these chips are most likely
Cuban. Most of the orders on that mold in that time period were Cuban."

The problem in the past with the Mason records is Inlayed chip orders are not in the available records, only hot stamps.
I will send for a Mason ID but doubt HH has it.