Jeff,
If your air cleaner is like the one on the upper left of the page at my link above,
Jim Carter sells a beautiful match to the original spark arrestor air cleaner. He also sells a paper element replacement (but you could probably find that locally).
By the way, I doubt very much that the weight of oil bath air cleaners is the reason so many Rochester carbs warped and leaked (but, that's a good story).
Tim
