As is stated in the licensing lists, Junkers are still ineligible for Military Materials licensing. Any weapons dealings the Congress take part in would have to be outside Bretonia.
However, I am sure the AgNO3 processing plants on Harris would appreciate the extra Silver stocks, and the Tau Trading Licence is open to you. A fee of 25 million credits to be sent to BPA)Anvil or BPA)Schiehallion[CCD] will cover your ships for six months.