To give my experience on mad hatter....
I was looking to get a couple axle back pipes made.. I show up in my jeep, and 4-5 guys surround it. I walk in and the dude behind the counter is playing on his phone and doesn't see me. So I tell him what all I want and he throws me a "reasonable price". I look in the shop and it was a bunch of young hoodlums working on the cars. Place was disgusting. Ghetto as hell.
I know everyone says mad hatter, but I wouldn't let them work on a 96 accord. Let alone my jeep.
A place I used to use is Oz's Discount muffler.. I went there first. He moved to a different shop, and now he is just money hungry.. All I wanted was 2 exhaust pipes maybe 2' long each. I have done custom exhaust for 4 years and I knew exactly how hard it would be. He tells me a stick of 3" tubing is 100$, and 2-3 hours labor. A stick of aluminized tubing is NOT 100$. Well he then tells me how many cars he has to get done, and people not paying him for jobs he did.. I don't care. I have cash in pocket and your trying to rape me now.
Well luckily I still had a hook up at Midas, where I did custom exhaust for 4 years. I went back there and busted out 2 pipes, welded it all up within an hour.
Honestly I would look at maybe boost performance (they seem to be doing exhaust well)
Exhaust works ( a buddy of mine goes there)
FYI you can get stainless pipe, but I'm 99% sure you will not find anyone that will get galvanized exhaust pipe to weld.