We all know how bad a soft-top Suzuki is for security; THERE IS NONE! Well, when designing the LJ50 and LJ80 soft-tops, Suzuki realised that something was needed to stop people from picking them up and walking away with them. They put a lock on the handbrake lever, to keep the handbrake applied when the vehicle was unattended. This stopped them from rolling the vehicle away, but didn't offer any protection for valuables either (but this was in the days before iPods and mobile phones, so it's OK).
However, over the years when the LJ got handed from one owner to another to another, sometimes the key to the lock went missing (it wasn't the same as the Ign).
There is a seller who has these keys
Genuine on E-Bay! Read the 3 digit code on the barrel of the lock and see if the number is on his list.
Good luck, and save those LJs!