I’m curious what you found. I only found one - the alien stroker - it looks like it could be 100% silicone, but noticeably the description doesn’t clarify whether it is a blend or not. And there are 0 reviews.
FYI, if it is 100% silicone, you can boil it to clean it. If it is a blend (or not silicone at all), boiling should fuck it up.
I’m a fan of nitrile. Silicone is easy to fit because it tends to have a lot of stretch, but I find it also tends to pinch a bit because of that stretch. Nitrile is still relatively soft and has some stretch, but quite a bit less than silicone. Less stretch means you need to buy the right size, but they are inexpensive and you can get multipacks to figure out what size you need.