I would say the one that I have would be $30 and any bigger size would cost you more obviously. If there is enough interest in this I could pick up some better tools to allow more refined finishing on the product. I'm very happy with my prototype and I'll try to post some pictures later.
Steven

I'd be interested in a larger size as well.

It is possible to make them into a larger size box with the consideration that you'll have to have the clearance between your tank braces. Also need to take into consideration that this will take up space in your tank and needs to have a place for it.

I'm more concerned about shipping to you, Lance.

Steven

Added pictures of sample products in the original post and please PM if you are interested in one and let me know the dimensions that you're interested in.

Steven