So I got me a box of Gorkamorka blunderbuss orks from ebay.
They had to have a nob, of course. Luckily I had one in my bitzbox.
Now I've been planning on making some pirate orks for a while, and found some nice bitz from Spellcrow. And also this:
A blunderbuss ork from Umbra Turris-game line, looks piratish enough to me. Also a bit bigger than them Gorgamorka orks.