Shit man. Wouldn't be too hard I can't imagine. Not sure on cost. Start at $1000 and we'll trim it down from there
hehe, just kidding. But really, too hard to quote. How does - cheaper than anywhere/anyone else - sound?
cost will also depend on whether you want stainless or mild.
Also, why does the exhaust loop around and come back on itself? That's a bit silly, or can it only exit from that side?