Like your namesake, you seem to have a touch for finding or doing the right thing at the right time. I won't call it luck, but you do have the touch.
About that particular one offered up by that site, I noticed that they have other 'blanks' for other makes, including ones that appear to be original and that were never completed with paint or enamel. I myself think it unlikely but (usually very) small caches of uncompleted parts do turn up from time to time, possibly from private 'collections' of former employees (and their estates) of the outside companies which were doing up the parts for the manufacturer.
(I myself picked up from such a completely unexpected source a pair of NOS and COMPLETELY unobtainium pot metal "check marks" that were only offered for two years on an extremely rare and extremely specific Studebaker sedan model--1956-57 "export luxury 6 cylinder short-wheelbase Presidents" W6 models--so rare that even the museum was unable to find any further information on these unknown W6 Regal models--which seem to not exist except for one reference in a parts book and some pictures of at one time extant cars and ONE German and ONE French ad each)
Did KF do up these pieces themselves for the HJ and Allstate? I am trying to judge the likelihood of part like this being NOS but unpainted...