Portable Murals?

[silverwing21.livejournal.com]

I have a question for you painterly types. I do oil painting and murals, and I was asked to do a halo mural for a computer store in town. Seen here, and here.

The funny thing was, they weren't really expecting much of a painting evidently. When they saw the finished mural, they were all very impressed. Now they would like several more murals done, which is great, but they want them done in some way to make them portable, so that when the store expands and they need a bigger building, they can take the paintings with them. Now, I'm all for someone wanting to preserve my work, but the murals a really big, and I can't buy canvases that large. I could make them, but they'd be terribly heavy and they'd stick out of the wall quite a bit, and quite frankly, the idea of canvases around a room full of 13-18 year old boys playing video games just doesn't seem great to me. Don't get me wrong, they're good kids, but they can get rowdy sometimes. So we want to find some way to make them flush, or close to flush to the wall. But I can't find canvas board that big, and piecing it together would look somewhat odd. And then there's cost. Do any of you lovely crafty people have any ideas? I thought about wallpapering canvas to the wall and then painting, but after we took it down, I'm not sure it would go back up again...