I need a headshell recommendation for Technics 1200 GAE

@rauliruegas That link is spot on. Easy to follow calculations. Any mass added over the stylus increases the effective mass by the same amount. 

Detachable headshells are a great way to fine tune the effective mass of the tonearm and cartridge resonance. 

@rauliruegas or anyone else, at the risk of beating a dead horse, I want to make sure I understand this.
My SL1200-G has a tonearm with an effective mass of 12 gr. The headshell is 7.6 gr. If I remove the stock headshell and replace it with one that weighs 12 gr. is the effective mass of my tonearm now 16.4 gr.?
 

@ericsch It will be close enough to 16.4g.

Another option which I used with an ART-9 is the Nasotec Swing headshell. It may appear quirky but it works very very well.. I sold my 2 SAEC ULS3x shells for 2 of these, and compared it to a Shun Mook recently, and much preferred the Nasotec. Not cheap, but you didnt mention budget..