In reality there were somewhat fewer Ithaca NID Super-10s built than the Magnum-10s.
Charlie Price presented a paper on Parker Gun Gauges Over the Years at the PGCA 7th Annual Meeting and Conference held at Cleveland, Ohio, July 21, 2001. Parker Bros. 10-gauge production peaked in the 1881 to 1885 time period at 11,632 guns, but was still less than 12-gauge production of 14,470. In the five year period after the Super-10 load was introduced, 1926-1930 the Brothers P only produced 84 10-gauges. From 1931 to WW-II only 15 10-gauges were produced to 2848 12-gauges. No breakdown on how many were Super-10s and how many Magnum-10s. You can see these late steel barrel Parker 10-gauges are quite rare and do command a premium.
