It'll fit, but all you need is the airbox lid and the starter cover.
That one on ebay is $40 (including shipping) for a bunch of extra stuff you don't need. Maybe a spare air filter - but you've already got everything else, right? I'd think you could find a cover for five to ten bucks and a starter covers for ten to twenty.
Give wirewrkr a buzz - he's got parts he sells. I'll bet he's got something for you.
By the way - all of the airhead air boxes are the same from 1981 to 1995. Some had one large and one small snorkle, but they're easy to swap. You need one large and one small.