Hey John,
Despite appearances, your 10K gold filled Cushion actually dates from the 1940s. There are some notes in the Hamilton records indicating that the 10K gold filled Cushion was produced from around 1940 to 1949 using 986 series movements, by then obsolete in the consumer line. The original version of the "Cushion" model was 14K gold filled rather than 10K gold filled, and produced in the 1920s.
The precise reason for producing these 10K Cushion models with 20-year-old movements is unknown, but perhaps it was a way to sell the obsolete movements, or to circumvent wartime restrictions on consumer watch production... it is defintely an area ripe for further research.
I've seen these with both 986 and 986A movements, as well as 987 movements. The case hallmarks (Wadsworth) are more consisent with the watches produced in the 1930s and 1940s, rather than the 1920s watches.
Another subtle difference is that the case shape is more like the 1930s "Cushion B" with short lugs, rather than the original "Cushion" case with long lugs.
I've seen some of them with luminous dials, but most have black enamel painted numerals with blued steel hands, usually without sub-seconds, but sometimes with seconds at 9 o'clock.
I seem to recall seeing one in white, but every other one I've seen has been yellow. I have not seen any green ones. There are also some notations in the records that some of the cases are vermeil, that is yellow gold fill over a base of silver... perhaps due to wartime critical metals shortages.
The records suggest that around 1200 to 1500 of these watches were produced, I'll check to see if I can narrow that down to a more accurate number for you.