What wire other than 1.6 mm stainless will work for chain mail?
I made a butted link hauberk some years ago out of galvanized steel wire (the stuff I got was used in repairing fences - 20 gauge).  Not as shiny as other materials but I felt it was more authentic looking.  It is fairly easy to form and cut.  The mandrel I used to form the links was 3/8" diameter.

When completed there were some 40,000 links in it and it weighs around 40 pounds.  I wore it over a gambeson I also made.  The hauberk comes to about the groin (worn with a belt to adjust the weight somewhat) and to a few inches above  the elbow (I'm 5'10").  

I wore it numerous times to SCA type events and reenactments but never did much mock combat with it.  I never had an issue with links stretching or popping out.