If you don’t want to splurge, your best bet is this J.Crew Rollneck. It's a popular item, while not very costly. Another strong contender for your wardrobe is this J.Crew Turtleneck. While the price of this item is not very high, it will surely attract a lot of attention.
For something in the middle of the price range, you're in luck with this J.Crew Turtleneck in stock and waiting for you. You most certainly will love this piece.