Steve,
I think you can depend on the markings. It will almost certainly say "multi-coated" on the binocular if there are any multi-coated surfaces at all. Of course, there won't be any multi-coating on any of these made before the mid to late 1980's. What you have to worry about in these old binoculars is no coating at all on the interior surfaces. You can be sure if they are marked "coated" that some, probably most, surfaces are uncoated.
Here's what the "Japanese Export Inspection Standard for Prism Binoculars" required the coating marks on binoculars of this vintage to mean, from J.W. Seyfied "Choosing, Using & Repairing Binoculars", p. 147:
"1) In the case of binoculars marked COATED, at least the inside or outside surface of the objective or the inside or outside surface of the eyepiece shall be subjected to anti-reflective treatment. 2) In the case of binoculars marked FULLY COATED, all air-to-glass surfaces of all lenses or prisms shall be subjected to anti-reflective treatment."
Henry