AFAICS it's a Euro Cylinder lock.

You need only change the cylinder. Some of the sheds do them (beware
they come in different lengths, 2 dimensions to measure, see below).

It is retained by a single screw which screws in from the face of the
door.

http://www.era-security.com/H&A_EURO_CYLINDER.htm

Plenty of suppliers on the internet.

DG

I removed the said screw and indeed the barrel does come loose but won't
pull right out, even with the handles removed.

Fading light, hunger and rain dictate I'll have another go tomorrow.


david