If you lived near me there are a couple plumbing stores I'd recommend. They do business in hottubs, irrigation, plumbing supplies, pumps, etc. Look for a similar business in your local directory. Larger hardware stores would probably carry it as well.
If you can't find anything, some hose clamps and a piece of hose and you might be able to make something yourself.
"The important thing is not to stop questioning. Curiosity has its own reason for existing" A. Einstein
"Life is either a daring adventure or nothing."
"We can do anything we want to if we stick to it long enough." Helen Keller