Neil,
Beaut pen timber goes well with it you made a pen to be proud of.
Now I gave my Hollis twelve guage to a friend a few months age and I had not used it in a long time so being out of the loop so to speak I am not familiar with the colour of 12 vguage cartridges in your country but their are many pure colours (read reds , blacks though not a colour but a shade, ) that would hit like a hammer the imagination of shooters and create a demand you will be flat out keeping up with, then with these in display any variety of blank will sell once the impact is seen on the solids.
Just a thought friend from someone who needs a nudge sometimes then has to have.
Kind regards Peter.