I’ve done some further modifying and reduced the markers down to 32 mm x 32 mm (about 1 1/4 inches square). Anything smaller and it wouldn’t work, but I have a feeling this size could work for most territories, as I imagine there will always be some that are just too small, no matter what, on an OOB game board.
For reference the original task force markers are about 36x48mm (about 1 1/2 x 1 3/4 inches rectangular).
IF there is interest in this, I’m thinking ca$6.00 per set of 6 (approx us$4.65 right now) but that is not set in stone (could be more, could be less, largely depending on the quantities and the cost of getting the proper cards made).