Suggestions:
System has the provision to map a pricelist to customer as per location/site. User can use Site Customer master.
In Site Customer, User can enter code of the site to which access of customer to be granted. Along with it user can enter, code of the customer to which business access to above site to be granted.
User can then select the price list applicable to the customer for the particular site.
In Excise clg Price List field, user can also select Price List from Price List master
In Price List discount field, the discounted price list applicable to the customer for the particular site can be selected.
Site customer menu exists in SCM module, SCM Settings, Masters, Customer, Site customer.