You can pretty much use any correct length 3d+, 3d30 rotor crank and buy the 144mm spider separately.
I personally opted to take a Dura Ace 172.5 (solid) and cut it down to 150mm. At my height 5'4", it allowed me to run a bigger effective gear (gain ratio) than when I was using a 165mm. 165 or 170 is okay if you can spin and finesse a lower effective gear, but it didn't really suit my high torque mashing style.