If it had the headstock decal shown in your picture link it was manufactured in 1985. Here are the '85 models:
http://www.tokairegistry.com/images/catalogs/tokai854.jpg
http://www.tokairegistry.com/images/catalogs/tokai855.jpg
From 1986 they looked like this:
http://www.tokairegistry.com/images/catalogs/tokai0001.jpg
In '85 all of the MAT's had FRP (fiberglass reinforced plastic) necks/bodies. In '86 they also started using carbon fiber necks/bodies in different combinations with FRP and wood.
I have two MAT's, one is a prototype made in '84, it has a copper chrome body and a black neck like the ones in the second link above but with a H/S/H pickup configuration (never offered on the production guitars). The other one is a red M-451 that had a bad neck (impossible to get straight). I bought it because I had found several unused MAT necks for sale here in Sweden. The 451 now has a 1986 carbon fiber neck with an ebony fingerboard and it's a great guitar with an excellent tone and sustain, I love it!
Regarding the headstock decal I'm afraid you'll have to find someone who can make a replica.
Mike