Either eBay, craigslist, any Jeep board, or a place that does reprints (like
www.books4cars.com, I think.)
The 88 Jeep FSM was re-issued by ChryCo, so you can find it in either Chrysler (softbound) or AMC (loose leaf) issue. The 84 will be an AMC manual, and will be loose leaf.
Meanwhile, if you have anything you need to know, I can probably dig it up for you. My collection is by no means compleat, but I've got from 1960 forward (and specs from most manuals are on my site for your reference as well. Link in sig.)