Re: Unable to find a part.
There is a temporary fix if the part isn't leaking. Separate the shell halves and insert a partially inflated balloon that's had the umbilical heat sealed in something like a Food Saver, then close the the thing up again. Your pressure pump will fill the cylinder and partially compress the balloon until the pump reaches the cutoff pressure. So long as the cylinder itself doesn't leak and the cutoff pressure isn't too great, you'll be surprised at how long the fix lasts (carry spare balloons). BTDT...
"It is not so much for its beauty that the sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."