most lhs's carry everything you need in stock, including the motors. i believe helifever usually keeps good stock of the parts as well.

all you need is the motor and a prop, not the silly "gws dd tail mount". the gws tail mount is actually heavier and weaker than the stock mount, which can easily be modified to fit the dd motor. you simply elongate the screw holes until the motor fits (mount the prop backwards as a pusher). btw, make sure you get the high voltage "x" version of the motor, not the low voltage "h". the x will is more consistent and lasts much longer

a word on brushed dd props: most ppl are using a 4030 prop, which requires an adaptor to fit on the dd motor. i found the 4030 performs well, but a bit too much prop for the motor, so i use a 3030 and a heatsink to keep the heat in check (it is also lighter since the prop adaptor is not needed). the difference in performance is hardly noticeable, and the motor lasts much longer.