Most of the time, you get what you pay for when it comes to tools. Something like a micrometer, I would spend the extra $$$ to get quality and accuracy. I have a digital torque wrench and they are worth the weight in gold. I got mine from Snap-On and it beeps and vibrates when you reach your desired torque level. It also shows real-time what the torque reading is.
Some additional tools I would get (some of them are just nice to have):
-O-ring and seal pick
-telescoping inspection mirror
-piston ring compressor
-piston ring gapper
-Torque angle meter
-Tap and die set for the unfortunate events
I'm sure you probably have these already:
-Catch pan for various fluids
I'm sure there are a lot of things that can be useful. The more tools you have on hand, the better.
Good luck with the rebuilding of the engine.