There are a couple of ways around the zipties. One is to use a reflector clamp like these from Cateye. Measure your fork diameter and find the clamp that works. Relatively cheap and quite secure.

You can also use a shock fender. SKS Shockblade fenders are easy to mount and do a good job. They don't cover as well as a full fender but they will do the job and don't require stays.

Bikepedia does show that a 94 Hardrock was a nonsuspended bike. The 94 Rockhopper had a fork or perhaps the dealer put one on before you bought the bike. Not that it matters much. You probably don't need a suspension corrected fork because the forks from 94 had 80mm of less of travel and, often, suspension forks were added to unsuspended bikes anyway. A noncorrected fork will make the front end slightly steeper but I doubt you'd notice much.