I think another consideration is whether attributes like the PO ordering agency or the line item copy's owning library should be used to filter the set of available funds. Ultimately, zeroing in the right answer in the specific case of the funds drop-down may need to be spun off into a separate bug, but I think the notion of teaching eg-combobox to pre-filter by permitting OUs has wider applicability.
I think another consideration is whether attributes like the PO ordering agency or the line item copy's owning library should be used to filter the set of available funds. Ultimately, zeroing in the right answer in the specific case of the funds drop-down may need to be spun off into a separate bug, but I think the notion of teaching eg-combobox to pre-filter by permitting OUs has wider applicability.