1974 S$10 Map Mule Coin

True, NGC has certified two in MS-69, but they have also graded 20 others in grades ranging from MS-63 to MS-67. Of these, seven have been assigned grades of MS-64 and five have been given an MS-65 grade. PCGS has also graded >20 mint state examples of this mule.

I would treat the 320 number as an estimate of mintage vs. an absolute figure - while Canadian Coin Digest lists such a mintage, the Charlton Catalogue lists the mintage as "unknown" (at least in the most recent copy I own). I'd be surprised if the RCM knew exactly how many were produced.

One sold at auction a little more than a month ago for $470 USD; it was graded SP-66 by PCGS; another (an NGC MS-64) sold back in November for $423 USD. A recent ebay sale at a higher price seems to be an anomaly.

The European connection is a result of the coins being part of sets that were sent to Europe to be marketed there by Lazard Freres, a Paris-based financial management and investment firm. LF was an international marketing partner to the RCM for the Montreal Olympic coins and handled European sales.

I look forward to seeing your coin once NCS returns it.