That's brilliant, thank you!
I have no idea when the alarm was last serviced - perhaps never. I know that the old owners used it and reported no issues.
At a minimum I would want to do a like-for-like replacement for a panel which isn't bashed and dirty. Would this be a simple job (ie read the manual, disconnect old one, reconnect new one with wires in the same place) for someone utterly unskilled (can wire a plug, not much beyond), or would I need to get a professional in?
If there are upgraded versions which look more modern, have features such as unlocking with a keyfob / wifi connection then I'd be keen to upgrade to the latest version. I've got no appetite for a complete rework of the system - good enough is good enough for me.
Thanks for your assistance in identifying it - wouldn't have known where to start otherwise.