Hondahookup.com has one for download. I believe it's the 1988 version and possibly European spec (has ZC DOHC as well as rear seat details). Even still it works great for my 89 si.
Also keep an eye out on eBay. I got an 89 helm manual for only$20 shipped. Just don't get fooled by the electrical troubleshooting manual that looks exactly the same.