Murmansk69 wrote:
I've got a really narrow cold chisel which I am using to remove the
mortar between my bricks prior to repointing but some of the bricks
are really close and I need something narrower - about 4 to 5 mm
wide.

Does anyone know where I could get one as I've so far failed in my
search.

I had the same problem and used an old screwdriver. Mind you, the stuff
I was removing was pretty soft.