I bought a Dynomax 17676 muffler from Jegs in March for $63.99. It was installed in my S3 and was run for ten miles. It is in excellent condition. It was swapped out for another muffler which has the same muffling capacity but looks nicer, cost more, and I didn't want. (This is a result of the unethical behavior of a particular aftermarket exhaust company.) The muffler body is a flattened oval 9.75" long and 4.25" inches deep according to Dynomax, while Jegs says it's 4.5" deep. Overall length is 14" with the outlet and inlet pipes which are 2.5" in diameter. The exhaust pipe on my car is 2" and easily was flared to 2.5" to fit the muffler. I have a stock Elan muffler which is 3.75" deep with attached pipes 1.75" in diameter.
The Dynomax is for sale for $45.00 plus shipping.
Send a PM please.