I put a bolt together Walker system on Pickup from NAPA and it works well enough. The fit was not terrible, one pipe to trim to length and I ended up customizing it with a length of flex pipe in the middle. It wasn't expensive, about $350 including the converter (my truck only has one and the whole system is much more simple, so I doubt it's comparable). Just slightly louder than stock.
That said, I'd hit a shop and have one bent up, although maybe check prices on catalytic converters and get one yourself. Amazon has them pretty cheap, for example.
'91 Toyota Pickup
'09 Kawasaki KLR650
'12 Gunnar Rockhound 29
"They say the test of literary power is whether a man can write an inscription. I say, 'Can he name a kitten?'" -- Samuel Butler