Most of the Portuguese Artillery used in the Peninsular War, namely that of the Lisbon defense lines ( Linhas de Torres) has been totally built in the national arsenals, being several fire mouths (as we often call cannonry) cast still in the second half XVIII by Bartolomeu da Costa (the same one who cast the howitzer with the pompous Chinese bed) and Italian born Carlos Napion.
We are talking about 150 fortifications (redoubts), held by 27.000 men and 380 artillery pieces, namely 24, 12, 9 and 6 pounders and 5 ˝” howitzers.
I wouldn’t know (right now) if campaign artillery had a different procedure in terms of provenance.
… But i can post this link where, besides the plant drawing of various Portuguese foundries and uniforms of gunners, you can see, as from page 72, a few Portuguese Campaign pieces: a 1 pounder light cannon attributed to Master Bartolomeu (1798), a 3 pounder from 1797, a 9 pounder from 1802 (on the wrong bed) and a 6” howitzer from 1778.
http://repositorio.uportu.pt/dspace/...e%20Anexos.pdf