Does anyone know where I can purchase C33 cable rubber protective boots. The trim tab indicator cable shows what I need. Stainless Marine does not sell these anymore. Thanks for your time.

Based off your pictures these at McMaster may fit the bill. The light duty heading.
I don't know how thick your originals are compared to what they call the light duty. It appears based off guessing the diameter of yours that'd be the only ones to fit.

Otherwise, if your Google skills are weak maybe call this place and see if they have any shelf items that they've made before that would work.
Flexible Industrial Rubber Bellows and Hydraulic Cylinder Rod Bellows – Crushproof® Tubing

Thank you for your time and your hyperlinks. I forgot all about McMaster. Unfortunately going through both sites I didn't see the size I needed. I probably should have posted that for people willing to go the extra mile like yourself. The ID size I need is at one end 3/8 and the other end 3/16. (probably could get away with 1/8) With a working length 5 to 7 inch.

At the end of the day what are they really "protecting"
I`ve never had any such boots on any of my boats and I didn`t die.
Hope that helps.

Why would they be needed on Morse 33c cables???

If the bellows are installed properly. They keep the salt/water from seizing the cable overtime. If they are installed with the plastic ties that come with them. They leak, holding the salt/water in place and the cable seizes quicker. Without the bellows the water does drain somewhat from the cable. And the cable still corrodes.

Dave,

You could probably make Oetiker clamps work, instead of zip ties. Amazon has variety packs and bespoke pliers.

Thanks. Brad.

That's an idea. I have used silicone with great results. But now I need four bellows.
I called Formula boats to see if they had replacement bellows. Left message because everyone was gone. Still waiting on a reply.

It sure looks like these would work in conjunction with oetiker clamps
https://www.ebay.com/itm/204568878374

Thanks for your time. Series 40 cables seem to be a lot bigger and diameter than c33 cables. It's a shame that the seller doesn't put any ID dimensions for it ends.