I keep an eye out for those ratty sleeping bags in garage sales that don't sell.often the owner will give them away to get rid of them. If you don't need to store the wheels on the bike (and you almost certainly don't need to), and loosen the bars to turn them this works fine and you can stack them in the back of a car or van for trips, too. Watch the zippers on the bags. These may not be waterproof like plastic (some are water repellant), but I like that. Less inclined to rust that way.
For shellacking cloth bar wrap, I buy the smallest can of shellac I can, use it and toss it, it can be ruined by drawing water. Amber over white wrap will come close after about 3-5 coats to matching a Brooks Honey saddle. I've heard you can dye the shellac with Rit cloth dye, too. If you like the tacky Velcro like tight grip this process gives on your gloved hand, fine. If not, sand lightly between coats. I used to do a lot of this, but in recent years I have come to love the feel of leather on my bars and the leather virtually never wears out so I have gotten away from shellacking.
Tom Sanders
Lansing, Mi USA