There may be more original EMM paperwork or microfilm of such, but I don't offhand know of them.
I looked at the single EMM card that I found online and told you about. I overlooked David Orr's age which is given as 32 at the time he enrolled on 13 September 1862.
I attempted without success to look up Orr and his company officers in the 1860 census. I was hoping to determine in which city ward he lived by finding two of them or more living in the same neighborhood. Unfortunately, I could not locate either Orr or any of his three company officers in that census.
Also, although the EMM card I examined online said David Orr was entered upon active duty on the day he enrolled, nothing there tells me what were his duties. I would have to refer you to the list of duties EMM members customarily performed that I mentioned in my last reply.
That's about all I can tell you from the evidence I found.
Bruce