Eaton's papers are in WO97/4757/102, although, you would need to actually be at Kew, to have free access to digital copies, otherwise it would be via fold3 or fmp, they are not available from their own site.
Addie wrote: Hello djb,
Thank your for replying and giving the information. Can you tell me please if there is any particular page, or search topic at the National Archives for access to my grandfather's military records? I've done a quick search but achieving 0 results.