I have heard good things about Walker.

A quick search on the site ( or in g00gull including "astrosafari.com" ) will yield plenty of threads here and suggestions / prices galore.


ps:
Alturas PD - recommending NAPA... up on the hiway, has Walker.

I get paid $.16 a year to schill... professionally, of course.

 

Recs come a dime a dozen. In the end, what are YOU looking for?
Quiet?
Loud?
Inexpensive?
Longevity?
Oem fit?
Have to make fit?
You can call muffler shops and ask for a price based on what they would put in which is typically an OEM style replacement. They may have options to choose from as well.
As far as self installation goes, what kind of tools do you have? Installing the new one is usually pretty easy. It's the getting the old one out that is difficult. the bolts are usually rust welded together and often need cut. They are hardened to an extent and often need a disc grinder cut off wheel or oxy/acetylene torch. You will burn through hacksaw blades, but they can do it if you can get them in.
Mind you, unless you have a lift, you will be laying under the vehicle with all the rust and dirt falling in your face while doing so. Use jack stands or ramps, where goggles, and maybe a dust mask.

 

Less and less exhaust suppliers around, probably because factory exhausts now last so long. Plenty of aftermarket mufflers. it's kinda simple, the cheaper the muffler, the shorter time it will last, especially if you live in a rust area. A used GM one from anywhere will probably last longer than aftermarket. Pretty sure what I welded on my 94 was off of a 5.3 chevy pickup.