These prop bank notes were were printed to be used in Cairo scenes where Sallah pays off the local diggers and when Indy and Marion are shopping in the Cairo Bazaar. Both of which ended up being either written out during filming or deleted from the final cut.
Each note has a unique serial number printed on the back and is made from a thin newsprint type paper. While it is not known how many were printed, at this time only three notes are accounted for.
CoA: Moviebits