K&N makes a replacement intake set-up, and I think there is another one, they run about $250 for th kit.

This is what the K&N one kind of looks like in my '90.
I turned it into a cold air intake system, all you get with the kit is the filter, tube, mounting plate and some brackets. It helps a little, but don't expect too much HP gains, you have to do several things to the 3.0 to get good hp increases. I am running headers, exhaust, cold air intake, a jacobs ignition system in mine, as well as having the cylinders bored .020 over(from hydrolocking it when it was new). I am not sure what the actual HP gains are, but I know it is a lot more fun to drive than my 22re(stock engine) X-cab which weighs about 1200lbs less

Google results turned up these companies, not sure how many are street legal here in CA.