Just a small suggestion... I think if you got rid of that rubber recoil pad and made one of matching copper-brass, that would tie it all in better. It just looks out of place to me. But, it's just a suggestion.
I agree. I don't have any copper or brass at the moment that would work for that size. I recycle materials, something will eventually filter in that will be a good fit for the recoil area with a little modification. The only non-recycled parts in this are two copper reducers and two washers, oh and the lighting. There is some aluminum in my shop that would be large enough for a recoil pad. With a little dressing up, that might look nice.