Greddy lists the solenoid for $99 (I presume the one linked to below is the correct one: p/n 15900535):
http://www.greddy.com/products/displ...SubCategory=51
It's possible you could fit a different solenoid to the unit such as the one sold for the MAFT Pro which runs $70 or so.... I don't see why not, but it's at your own risk.
The dude laughed? Seriously? Where did you buy the controller?