I'm addicted to Thorlo socks but they are $$$$.

I found some on 6pm.com, but they are a 9. The sizing chart says up to size 6.5. I'm a 7.

At Nordstrom, I can get a size 10 and the sizing chart says they fit shoes sized 7-11. But they are so much more expensive and shipping is a joke.

Do you think the difference between 9 & 10 is really a big deal or should I suck it up and pay the price for Nordstrom?