This thing about official military upgrades comes up from time to time. I don't think it is practical, or has been done, but there are certainly a couple of companies that have a scheme in place. Perhaps if you wanted a whole fleet of 100+ vehicles done then it would be a reality (at a cost)
http://www.saymar.co.il/Pinzgaure.htm
http://www.hpo-export.com/pinzgauer.html
Please if anyone has any other hard information and not just hear-say please post what you find.
jarvarisgoss cann you please name the company in Austria who are offering this conversion and perhaps provide a link to their web-site.