Call around, the guy youre asking might be dumb.... I would *think* any of the explorer GT40-style intake gaskets would fit since theyre basically the same lower plenum design I believe, staggered circular ports....but dont take my word.
Dont you have an old one you can just bring in and match? Or hell carry the whole upper plenum in and match it up, thats what I'd do.
here's a picture of my lower from a 97 explorer...i'm not sure if the 9th hole was on the cobra lowers...i'd check your lower and then ask for a 96 and see if thats right....if its not, ask for a 98 (96/97 was a split year i believe??)
this thread covers the gt40 intakes pretty much...