The seal skin/fork skin won't work on the TW200 front forks and here's why;
The space between a bottomed out fork and the lower triple clamp is so small, the skin / seal will bottom out the fork well before the fork actually bottoms out and tear the skin. If a bottomed out fork had a couple inches, then it would work, but they don't have even 1/2 and inch. And even less than that if you have the fork tubes sticking up out of the upper triple clamp more than just the cap of the fork leg.
Here's some photos of a fork with the stock boot with dimensions. I am illustrating that even boots barely have the room to work;
First a photo of an installed boot with the upper clamp loosened and slid all the way down and completely compressed;
In this photo, the bike is on a stand so the front suspension is at maximum extension. I hold up a scale and you can see that there is slightly LESS than 6" of fork travel before the boot bottoms out against the lower triple clamp;
This photo shows how much of the fork leg sticks above the upper triple clamp when measuring the available fork length in the previous photograph;
The fork travel spec is 6". Meaning; even with the factory boot, the boot will bottom out before the fork will. With skins, the bottoming action will damage the neoprene material skins are made of. At least, that was my experience.
What I have searched for and can not find are this type of fork boot, called a dust boot;
I've come close, but the groove in the lower fork leg on the TW200 doesn't match up with anything else I can find that will fit the lower fork tube diameter and the upper fork tube diameter.