In my opinion your assumption is correct, they are Starr variants however you are looking in the wrong place. Look at the British Sharps in the Stelma Book, 02-091 and 02-092 it has been discussed before and I believe that the so called British Sharps are simply Starr Variants. Notice the similar size and profile of MM53, MM202, MM68, 02-091, and 02-092 not to mention the exact same bases on the last four.