kodak will happily sell you Vision 3 500T. they will not let you repack and sell it as "eastman" "Kodak" "Vison" "5219" or any variation. They will tolerate CineStyle, mo-pic CineColor 500T and a host of others. they seem to be tolerating many folks who advertise that their product is "Made from" the actually Kodak product as long as the dealer is clear that the Various Kodak Trademarks ARE indeed Kodak Trademarks.
Eastman Kodak list a 400ft 35mm roll of 5219, 500T in their catalogue. just write ei-order@kodak.com and tell them how many rolls you would like. https://www.kodak.com/content/products-brochures/Film/VISION3-5219-7219-sell-sheet-EN.pdf
even with the REM-JET removed, the ECN2 films are really not a subsitute for regular C-41 films. with the RemJet removed before exposure, they are a find demonstarion of why film needs an auto-halo strategy.
Removal of remjet speeds up the film. So it’s not all bad.
Artisanal labs should consider selling straight Vision3 and develop ECN-2.