Well, the 1/16th Scale M3 Stuart available from Shapeways appears to be a scaled down version of the popular 1/6 scale model out there....even replicating some of its minor flaws and inaccuracies (very fixable). This later type M3 Stuart was used extensively by the US; but, I have to say that I would rather have a model of the earlier M3 used by the US and the British in North Africa - if I could choose....
Anyway, it appears to get the one on Shapeways you would also shell out $400.00 for the parts they have available - and not all are. And, then convert those bits to an RC model. That is a bit rich for my liking.
I noted one or two 1/16th Lee bits on Shapeways as well (???) Not enough for me, but maybe someone is in the process of making one?????
I very much like and use Shapeways for add-on and detail parts; but, larger parts seem to be VERY expensive for them to manufacture - at this time.
I have to say that I am sort of hoping that Trumpeter would make one or two US/Common Wealth tanks in 1/16th scale to offset there German kit line......
Anyway, best wishes,
Springman