Like Bio said, ZZP sells it and after you buy everything needed for the kit, it will cost at LEAST $1600. That kinda sucks considering the SSM90 kit won't make much hp compared to top swap or turbo cars.
Here's my recommendation though if you do go the SSM90 route. Get an L67 balancer so that you can run a normal sc pulley rather then the SSM90 pulley. You won't have as much belt slip and you will be able to squeeze out more power (considering that the smallest SSM90 pulley is either a 3.2" or 3.4").