build it yourself
out of regular plumbing pipe. Home depot has it. I've heard galvanized has a smell to it when it gets hot, so use the regular stuff. Take your old one off and bring it to the store and figure out what pieces you need. Reuse the old mesh heat-wrapping or get a new one at a auto supply store. The pipe should cost you less than $20. Or you could pay big bucks and get one made for you. The flange is costly so when you remove it be careful you don't break it. Don't forget to get some gasket material at the auto store too. My boat has the old Universal 5411 and that's what I'm basing this all on. I assume that yours is similar. Good luck, -Rob
