DOT3, DOT4 and DOT 5.1 are interchangeable.
DOT 5 is very unique and separate from the above three.
point is: - If you cannot find DOT3 brake fluid, you can use DOT4 without issue. - btw toyota actually goes off the japanese specification of brake fluid which is JIS K2233 - class 3 (which is equivalent to US DOT 3 brake fluid)
just like all screws on japanese cars that look like phillips are not actually phillips bit but are JIS cross head (chaar moo ka screw)
The picture above will explain you the reason why you see stripped or chewed up screws on all japanese cars, trucks and motorcycles.
POINT: Buy the right damn tool - its sold in tool shops (at least in khi it was)