Just a thought from my brain. Dunno if it would even work but I'm gonna spit it out.
Paper Mache. Cover the pipe with a thin, but protective, layer of plastic (I'm thinking glad wrap? something that won't hurt the pipe). Must be damn close to water proof. Wouldn't want any of the glue goop to reach the pipe. Then start layering gooped up strips of newspaper onto the pipe shape.
After you have a few good layers on there let it dry.
Carefully cut the thing in half as straight as you can. Using the aid of a clamp and cloths for a gentle touch to hold it in place maybe.
Once you have the Paper Mache shell off of the pipe I would mix an epoxy and hardener that I could pick up from a local store (Walmart should have these cheaply if you don't know where to go) And give the Paper Mache a coat or two with the mixture. You can use a paint brush but you'll probably have to throw it away after.
So after that dries you have a hard durable shell. You can fit the inside with some soft cloth. Cotton, felt, whatever you want. The outside will probably come out black, or gray, and dull. So... Feel free to get creative there. Paint over it or you could shine it up with some wax? lol
The shell thickness will be determined by how much Paper Mache you're willing to patiently put on.
I dunno, just a thought from a crazy guy with more than enough time on his hands.