Welcome to the forum Rob. I lived in/around Melbourne from '57-'98.
If you are looking for alarm to fit the '88, I don't think HD makes a fob system to retrofit. Gorilla makes a lot of different types of mcy. alarms. I had a friend that bought a Gorilla, and liked it. Gorilla Automotive Products - Lug Nuts, Wheel Locks, Auto Security, Wheel Accessories