Are you shipping the display or is it local? If shipping, the concrete is going to jack up your shipping charges. Same with the PVC if you could use Gator instead.
Is this going in a typical 10x10 booth space? Or is it part of a larger booth?
Are they reusing the display and graphics?
Any way you could post an image of your idea? I'm having difficulty picturing it from the description. What is in my mind is something like a 5x12 triangular monument sign in the middle of a booth, am I wrong? I'd be happy to throw out any ideas once I have a clear picture of what they are looking for.