I have a couple like the one in Jason's post, 2mm and 3mm. They are the cheaper Chinese ones from ebay. They use the MGMN– inserts which are common and not propriety types. If using a mill boring head, then a ground down drill of the shank size to fit the head would work. If you have any parting off carbide inserts, then it would be possible to silver solder one to a steel shank to make a custom tool.
Buying one at the moment from a UK supplier might be difficult.
Edited By old mart on 27/03/2020 18:31:26