1991 S-10 pickup with manual brakes. What you are looking for is the 3/4" bore wheel cylinder. Advance Auto Parts have them under Bendix p/n 33891. That's where I bought mine. About $25 each.
Yes...and it's not always fun in the rain when you have to brake hard. I rarely every drive my car in the rain, so I don't have to worry about it much.
They definitely help in holding the car on the line.
Just be warned that they may be feather tight. I did mine and when going in reverse just touching them would jerk the car. Looked like I couldn't drive.
I since went back to stock. If this happens to you, an adjustable proportioning valve may be of help.