I didn't get the chance to go looking for Prime over the weekend, but will this weekend when I take the kids to see their grandparents (who apparently live close).
Anyway I've give this CUBE thing a bit of thought and like the idea of etching (though it could take forever). I still have not found the true 1:1 of the graphic, so have begun breaking the 1/3rd image into the 6 sides.
So the plan is:
1. Import each of the 6 sides into SketchUp and scale them up to the 12" size.
2. I doubt I will re-draw each part, rather just cheat and print them out at their new size. They will pixelate, but that's OK for what I want to do.
3. Glue them onto the MDF and start etching away.
As I said, time consuming but it should look good once the graphic is removed, and it gets painted up and sealed.