So, trying to make sense of all that: Gouby C* is the 122 rim beads. The Spink coin uses obverse C*. Excluding the toothless border there are six varieties - the toothed, the three mules, the regular proof and the specimen. Also, secret santa, you say BP 1953 L and BP 1953 R have the same die combination but they are different in your table. The Spink coin appears to be C*+a (which is what it should be in your table too I think - reverse b would make it not a mule). Also, does the Spink Numismatic Circular shed any light on the origins on these mules?