One of my doors has such a lock, and the '60mm' appears to refer to the distance from the edge of the door to the centre of the hole for the barrel. The body of the lock is 93mm long and 62mm high.
At first sight, the one I need to replace looks the same as the type 77 - but the distance to the centre of the barrel is at 80mm (instead of 60mm), and the body is 105mm long (instead of 93mm. If I used the type 77, I would have to plug the original hole for the barrel, and drill out a new one (32mm dia). Unfortunately, the door has a skeleton frame (I don't mean the 'doorframe') with inset thin panels, and being 20mm closer to the edge, the new hole for the barrel might seriously reduce the strength of door.
So does anyone recognise the type of lock that I have, and who makes it? Google doesn't seem to provide any answer.