Is it possible to get BTH for my bitcoins that were in a cold storage paper wallet during Bitcoin Cash fork?
Yes. That's the entire idea.
https://www.bytether.com/register.html -- Just plug in any bitcoin address (yours), and it will tell you if there is BTH to claim or not. Then you just follow the process to claim them.
That said, there is a current issue. Not sure if it's bytether fault or etherscan.io problem.
It appears the BTH was in the registered address, and now it's not. Seem liks a goof in the matrix. Waiting on a response now.