I never have enough covers for my reels. I often misplace them, and I also own several reels that didn't come with any sort of a case. I found a great and inexpensive source of reel covers sitting in my top dresser drawer. I dropped a small reel inside a pair of my heavy-duty hunting socks and have since used socks for covers. Later, I figured out that by cutting the top elastic portion off of the sock, I could fit large reels inside. Socks that are meant for cold weather have a lot more padding and protect the reels far better than thinner socks.
Steamboat Springs, Colorado