Thanks everyone for your help. I did contact Rudy on Wednesday and he's to get back to me whether he has a muffler. All of the usual parts outlets...Advance, Autozone, etc, carry Walker branded exhaust parts and there's no direct fit but a few that are close. Looking at the pictures of the exhaust as fitted in a J, there's not a lot of real estate to work with so "close" might not cut it. But, we'll keep looking!