FWIW, I was able to find Scepter 20L cans at Bottom Line Military Sales. The owner called on the phone, minutes after I placed the order.
He asked "Are these for Military use?" I answered, "May I say Yes?"
He said, no, I understand your concerns and we can still work it out. Long story short, he had some in stock which were made before Arizona became CARB-compliant.
That was his only stipulation - if the cans were made before the state they were being shipped to went to the CARB standard, he could make the deal.
So I had to settle for OD green ones versus the Tan I wanted, but no worries there. I also ordered two of the water cans, and also the Viton seals which are necessary for holding gasoline (versus Diesel, which the seals in the cans are made for).