Wow, sorry to hear about your loss. Since AA is leaning all their kits towards the HKS blowers, that might be a good reason why they want so much. Did you try contacting Rotrex direct and ask if they can either direct you to a rotrex supplier, or have them ship you a rebuild kit? I'm actually quite surprised that AA didn't offer you better assistance other than trying to sell you a new sc.
What exactly happened?