If you'd rather not spend much, your best bet is this Bailey 44 Rollneck. It's a fantastic item, while not very costly. Another nice option is this Eileen Fisher Turtleneck. While the price is competitive, be sure that this piece will become an excellent addition to your wardrobe. Or you can opt for this Sejour Rollneck. This item has all the potential to become a powerful player in your wardrobe.
If you're looking for a bargain, why not take a look at this Equipment Turtleneck. While the price is very reasonable, this product is an easy wardrobe update. In this price range, you can also look at this Eileen Fisher Rollneck. It's an attractive option both price and quality-wise. And do check out this IRO Turtleneck! It's a very popular item and good value for money.