I've no idea of the history of mine, there are no markings to state the option, but I have seen H29 on a few with the same spec and some had an additional plate stating "Testmeter electronics No. 3A HPG 70/1". Note these rechargeable 427As are 230V mains only, the transformer doesn't have a split primary seen with the regular option 01.
The manual is a regular civilian one, part no. 00427-90008 printed in June 1983, the option 01 battery is not a commonly available type, this might be why it was removed & not replaced, or they didn't want leakage problems.
David
factory