Brockman Mellowtones. He makes them in different sizes and either glass or steel pack. Great prices also. http://www.brockmancustomparts.com/
Pep Boys sells them, there's also Smitty's. I have Smitty's and cutouts with a butterfly valve that goes to straight pipes. Both sound good either way.
I was going to go with cherry bombs too, but couldn't find 'em for less than $35-$40 each. I found Thrush Glasspacks at my local Advanced Auto parts,and were in stock. About $17. each.
Them Thrush (round) mufflers sound like a Queer running from a Horny Woman. Cherry Bombs sound good...and the older they get...the louder they get. The Cherry Bomb company is about 75 miles down the road from me in Loudon, Tn.
Down here Autozone sells cherry bombs and they have them in stock, I think they are around $22/$24 the last time I bought them about a year ago.
Any Cherrybomb muffler(Glasspack, Vortex, Pro, elite, etc) is available thru any midas, meineke, Autozone, Pepboys, Summit racing, Jegs and many others. There is a dealer link @cherrybomb.com
Hot rods of Norco California sell Smittys for $35. I got a pair for my 1950 Chevrolet. Its been a while since I'v gone there so I would call to see if their in stock. I know the place was catering more to the street rodders and muscle cars opposed to the rat rodderrs or traditional customs.
have brockman,s on my chevy (glass packs) and steel packs on my ford both sound great and been on for over 10 years
Running cherry bombs because I needed something right away. Not bad with a flattie and I expect them to get louder soon (the packing is crap) which I will enjoy.
I have a ancient pair of Cherry Bombs on my Comet, the exhaust needs to be replaced soon but it still sounds pretty good.