FAQ for
Commando (1985) More at IMDbPro »

Many rumours were spread over the last few years in regard to a possible unrated release. In 2007, 20th Century Fox released the long awaited extended version. Some cuts - probably made for the R-Rating - had been removed and a bit more storyline was included. A detailed comparison between the theatrical version and the unrated version can be found here.

No, it is not chainmail. It is wool or cotton according to Vernon Wells when he was asked at a UK convention in Nov 2004. If you look closely, particulary in the scene where Bennet is leaning over Matrix as he is tied to the table, you will notice in the close-ups that the vest is in fact cotton or wool like a string vest.

Very unlikely. It's been almost 25 years since Commando came out so the chances of a sequel would be INCREDIBLY poor.