I presume it is the roll tube? The good news is that other than the part getting stuck in the dump valve (unlikey, but if it does try to flush it all the way out) it shouldn't hurt anything rolling around in there.
Maybe try suspending a strong magnet on a piece of fishing line before traveling. The roll tube likely has a spring in the inside. Maybe the magnet will snag that as the holder sloshes around. At least you may recover the spring.
This won't help, but it reminded me...
A guy was visiting Maine. He went into the two holer outhouse. While he was busy a local Mainer came in, did his business quickly, and got up to pull up his pants. As he did, a quarter fell out of his pocket and went right down the hole. He peered in, took out his wallet, removed a twenty and tossed it down the hole.
The visitor exclaimed, "Why did you do THAT??".
The reply, "Ya didn't expect me to go in thar' just for a quarter did you?"
Happy Fishing. vic