Aftermarket parts do not exist for the first gen H body cars. You have to make them from scratch or make parts from other cars fit.
CAI can be made from just about any pipe that will fit with a filter on the end. Search the forums, this comes up all the time.
Another simple mod is to open up the exhuast with a high-flow cat converter and muffler.
And another is to upgrade the stock Magnavox ignition to a higher-powered Delco Type II ignition.
Again, a forum seach will yield all the answers you need... I think most of that is in the Techinfo section of the site as well.
RIPBC... Off to bigger and better things