I couldn't believe it when one kind lady scanned this and sent it to me.
I don't actually have a Pinnock 404, but I'm sure it will help someone out there.
Can't comment on copyright, but seeing as Pinnock stopped manufacturing in 1966 and there are a heap of people selling pdfs of Pinnock manuals I came to the conclusion that totally free distribution of this is reasonable.
I have several Pinnocks and they're all very similar up to the time Brother started using the name in the 1980s, so if you have a genuine Pinnock, this is likely to be helpful.
I disassembled the original pdf, cut it in size and re-saved it to reduce the file size. It is 1.67MB and available here.