Hello jak, and welcome to the forum.
I'm pretty sure that the 13th and/or 14th editions had a table showing the ECC (Earth Continuity Conductor, the then-current term) sizes for T&E cable. I'll try and find it later and scan.
We already have this table of Imperial cable current ratings from the 14th edition on the site, but it doesn't include ECC/CPC sizes:
https://www.electrical-contractor.net/pc/IEE1966_T3.JPG
