We've been wanting to find the same carpet that was installed in our last house. I was able to save a piece from when the installation was done before we bought that house and brought it to a local carpet store to get a match. It was unfortunately no longer available but we found an almost identical product made by Shaw, berber style with a high wear factor of 3.75. We beat that carpet up at our last house and it still looked great.
With the manufacturer name, style number and color, I set out to find the best deal on the web. It turns out there is a huge concentration of carpet production in Dalton, GA, "the carpet capital" of the US. If you search on "Discount Wholesale Carpet Dalton" in your search engine, a lot of the direct to the mill companies will come up. None of them post prices as far as I can tell but you fill out a form on their site for a quote and generally they get back within a day to quote.
I was able to get 7 quotes in no time and they were at a substantial discount to what my local carpet store could do, about 35% less on materials even with shipping costs. I was told be a friend who experienced the same that it's a strange industry where you as a consumer can more than often get cheaper prices than the local carpet store because of all the middlemen they go through. These mills are all able to make or source the exact same thing so there is a big advantage to buying online and finding a local installer. Every one of them also offered to store our carpet for as long as necessary at no charge until we needed it here.
Try this site to get multiple quotes at once:
http://www.carpetbuyershandbook.com/
Here are a few of the companies that quotes and were particularly great on price for us:
American Carpet Wholesalers
Becklers
Advantage Carpet
Georgia Carpet
Carpet Wholesale Outlet
Owen Carpet