Scorpio has a black MAS 8x3 in the 061 RJL head but only turned about 9500 enough to fly not enough for an ROG I wou;d try a 7x4
and 7x3 should punch at least 11K. The black MAS is not really that hot a prop
I guess just mess around with 7 or 8 inch props till to get between 11-12K The tornado 7x6 was a disaster you coulld see the blades
flexing back and forth not very stiff. As stated my blue MAS 8x3 is the one on the 074 12K martin