We stopped by Target and HEB tonight. Target had some Lego brand folders and notebooks on clearance. They weren't a huge find, but it's so rare that I thought I'd share.
But the cheapest ones I found were $5.79.
Just remember that not all stores have the same clearance or mark down at the same time. This store may have them at 30% off, but another might be at 50%-70% off. Let me know if you find any and how much they were!