If you check out my USMC Sherman Tarawa thread in the Diorama section, there is a Japanese pillbox on the base...Masterpiece Models mistakenly sent me the 1/35 one instead of the 1/48...but let me keep both.  It came as you see it...one piece.

The one hitch is that while I was painting the 1/48 one, I figured I'd save work later and paint them both at the same time...but other than that, it is untouched.  I bought the LVT-4 and a couple sets of figures so I could have it loaded with a Howitzer moving past the pillbox.  I was hoping to build the LVT, Howitzer, figures, and base for the contest and then weather the heck out of the pillbox and add it in, but you kind of answered already I guess...I can't enter it now.  It would have been a pretty epic build though!