Sourcing Rule Set Up for Customer and Item

Hello all,

I was wondering if anyone had any ideas on the best way to set up sourcing rules to fulfill the following request.  We would like to use certain sourcing rules based on the customer that is ordering the product.  So if Customer A is ordering Item XYZ it uses Sourcing Rule Set A, but if Customer B orders Item XYZ it uses Sourcing Rule Set B. 

Example:

Customer A orders item XYZ it sources to Supplier ABC - Site 1

Customer B orders item XYZ it sources to Supplier ABC - Site 2

*Supplier ABC is the same supplier; but we want to source to different supplier sites, hence the Site 1 & Site 2