Looking for 4mm ratcheting spanner (for 3D printer nozzle replacing)

My 3D printer nozzle recently wore out and needed replacing:
https://i.imgur.com/MCbITECl.png

I went to a few tool stores, but could not find a small ratcheting spanner in the appropriate size.
I know it exists because the computer tech who removed the original nozzle due to factory tightening had the tool on hand.

According to the sales clerk at one of the stores, this is a 1/7th hex nut and the smallest tool they had was a 1/8th.

Does anyone know where I can buy the appropriately sized tool?

It's a long shot but try a hobby store that sells RC cars

Maybe try Jaycar?

Jaycar was the first place I tried.
They did not have the tool.