AP Accrual Acc defaulting need to be changed

In our current setup, we have a blanket purchase order for OSP items in our XXX organization. When OSP reqs/releases are made (automatically as operations on our wip jobs), they pull the AP Accrual account information directly from the organization defaults.

However, we now have two different businesses that transact in XXX. They each have different AP accrual accounts. So we need a way for the system to pull the correct accrual account (possibly a setting on the org item or in a purchasing workflow that will allow us to do this).

Please advise on how we can best accomplish this task.