Forum Moderators: skibum
You may be able to license the system from another company or try to pay them to customize it for you.
Try searching for "subscription-based affiliate program" on Google and see if those companies have their own internal system or if they are outsourcing (out-housing?) to others.
I have quite often found my best merchants in this way and we usually start with a small test of traffic, measure the results, adjust, repeat, etc.
Try searching for your keywords in the SEs and then contacting the websmasters to find the existing affiliates. Or some well worded stickymails to known big players through forums if you prefer.