You could also use the Thunder Tiger RC carbs from their .10 and .15 engines too. I put a .10 carb on a Russian MK-17 2.5cc diesel a while back and it worked OK for me.
There are some small throttles made for the Mills .075 and 1.3cc engines that pop up for sale from time to time too. Red Fin Engines in the UK sells small throttles that fits the Red Fin engines too. Cox Engines in Canada has a little throttle body made to fit the Cox .049 engines and it would work in some cases with other engines too.