I had noticed AN is now selling that exact same peg spanner tool 06.3965 Norvil has listed for many years now. (I got that and a few other tools from Norvil)
The single use tool being separate. NM23441
I guess it is one of many UK made parts/tools from independent manufacturers same as the clutch holding tools.
The good thing (imoo) about the peg spanner is it has the brake caliper tool also.
The caliper can be put in your machine vice (with appropriate protection) and the mill quill can be brought down to bare on the tool top face making removal or installation of the plug easy with no pin disengagement.