Not sure if you checked Safavieh's website, but I would think it would have the best representation of color. Though even from one computer to another the color can look different. I did not see an 8x8 square rug listed though.
I have five of their woven indoor outdoor rugs that I purchased through Overstock.com and I noticed that even on the same website I found a variety of color in the photography when looking at the same style and color rug in different sizes. I read the reviews, checking for references to color and used that when purchasing. I was very happy with the color when they arrived.

Here is a link that might be useful: Safavieh Lyndhurst rug

I responded to your earlier thread, but I didn't mention color. My Lyndhurst are more rust.....definitely not burgundy.

To check the color of the rug, you might want to order the rug in the smallest size available. This way you get to check the color, and if it doesn't work, sending it back doesn't break the bank. Also, if you're doing the complete room, you have a sample to carry with you the furniture stores.