There is a product called "rubber care" made by Wurth. I was given a can from a friend so don't ask me where to find it. It comes in an aerosol can.
It is very good. Follow the instructions on the can.
Might want to post pictures of a nice looking one before you ask for that kind of money. I did'nt see, is that stainless? What is the wall thickness of the tubing?