In my opinion rmatv is the best option available for you as I have used for my machine. You can simply buy seal packed rmatv without any hesitation and I am sure it will work for you for the next 30 years.
I would also vote for michael as I have used rmatv and I found this 100% reliable for me. I am not sure about 30 years because I have used this recently, but I hope it would last at-least 20 years. Thanks.
I did my fronts this weekend, pretty easy with a clean bench. A little penetrating oil and some air to the bleeder hole, and the pistons come right out... Watch your fingers! Once one of the pistons popped I cleaned it up and smeared it with fresh brake fluid, then placed a socket (14mm ) to hold it in place to free up the sticky one. My bike is very low hrs, so all the seals looked great and re-used them after cleaning in SUPER CLEAN, careful not to tear (used wife's dental tools). Lightly sanded smooth (400) some electrolysis from two of the four bores and re-assembled. What a difference it made, apparently one of them must have been sticking a bit more and overheated/warped one of my rotors. When I spin the rotor it hits a slightly rougher spot.
I need a rotor if any that reads this has one for an '87 TRX