Intercompany process - internal requisition organzation issues

Hello,

I am testing Intercompany process between two OPERATING UNITS at Vision.

While I am creating Internal requisition, why I can see at filed "Organization" only two organizations, if at Shipping Network form I can see more?

Second question - if we need generate IR from ASCP, how can we set default source organization to M1 at Internal requisition?

I setup Sourcing rule and assignment set, but when I create IR manually, M1 organization is not default.

Thank You!

Monika