Google CPAP or medical supply stores in the area you are in. You may be able to get a replacement before you sail or at a port.
We had a cpap issue on a Bermuda sailing when my mom brought the wrong water container. That was discovered on the first night when the machine whistled and leaked and could not be used. She really needs it to sleep. I was able to find a piece that allowed her to use the machine and both of us to be able to sleep. I had to take a taxi to get the part. But it was worth it. It took google time, several phone calls, an expensive taxi ride and a visit to a tiny cottage behind a medical supply store in Bermuda…but it all worked out.
I posted this in your roll call in hopes you see it. Worth a try as it did allow my mom to get Some rest the second half of the week.
if anyone has a CPAP issue on a Bermuda sailing, call The Medical House. They were awesome.
Good Luck and enjoy your trip!