I happened to have a nps2222a lying around and did exactly as you suggested, worked like a charm. Thank you.
However, afterwards I described our solution here on another board and someone much more knowledgeable than me says it's not necessary: "There's no risk connecting a 3.3V output to a 5V input pin. The reset pull-up is about 50 kΩ, which will generate a weak 30 µA current through the ESD protection diodes of a logic chip running at 3.3V."
What are your thoughts?
My thoughts are that while he might be more knowledgeable that you he is still not very knowledgeable.
While you can wire a 3V3 output to a 5V input in this case he is wrong about the pull up resistor. On the Uno this pull up resistor is in fact 10K. This means you are feeding 5V through a 10K resistor into your 3V3 device at a rate of 170uA which is over 5 times what your "knowledgeable friend" said.
This is not a good idea at all, using a ESD diode as over voltage protection is some what of a hack and is not to be recommended. Especially when you consider that these devices are not designed for the abuse that the Arduino chip is. This is due to the smaller chip geometry.
I think you should get more knowledgeable friends.