Research on grade 417:

648501-649000,417,12,1,17,500,1910

648610 – posted by Robert Schussel, “in a SB Pilgrim 25 yr case with a SB metal dial. If the dial is original to the watch it is a very early South Bend metal dial.” – published on IHC185 website
648640 – ebay 29.08.2015
648701 – pocketwatchdatabase, reported as inaccurate grade 419
648738 – Frank’s Kutsumoto picture on IHC185 website
648829 – ebay 29/07/2018
648882 -Horan-Jones auction 10.07.2019, Pilgrim Chesterfield case, roman enamel dial
648947 – my 417, also Pilgrim case and metal dial.

Please let me know if you have seen any other serial numbers.