Stock pipes will be the quietest you will find. If your's is not stock, then you can maybe find some stock pipes on eBay, or even on the for sale section of this site, or try the Spyderlovers.com site and look at their for sale section. There is someone out there that put on some custom pipes and might still have the stock one available.......
If you do have custom aftermarket pipes, you may be able to trade someone who has stock pipes and let them pay for the freight.....