What head shell is a good match for the Nagaoka MP-500 cart on Technics 1200G

Good luck. It's a great combo. 

I have this exact cartridge/turntable combo and I use the stock Technics headshell. Been very happy with it.  

Do I need to buy tools to adjust/measurements on the vta and other adjustments? Or can I Google the specs on what the adjustments should be for the mp 500 and the 1200g turntable and that will be good?

Just set the top of the headshell in parallel with the platter surface, by eye or a suitable guide. That’s VTA. If you don’t own one you will need a stylus force gauge to set VTF. Consider a digital gauge. There are many for under $50. To align the cartridge there may be a gauge that comes with the TT. Otherwise there are a myriad of protractors that cost between zero and $700, last time I looked.

Without exception the OEM headshell yields the best results overall.  The proof is the measured resonance.  I have yet to discover an exception.  And adding weight such as Elliott likes with those little bubble thingys just makes things worse.  Being outside the 8-12 Hz range for resonance is all too common.