I see.
In FPCOPARA there is no field for output type instead, every output document should have correspondence type defined before it could be printed trough FPCOPARA.
That means you should define new correspondence type for your type of output document and than you could select that type in Correspondence selection tab under Correspondence Type field.
But, that would probably take more time than what you would need to find solution in VF31 transaction.
GL 
Mario