I think I might have found it. When the local video rental shop went under I bought up anything that looked interesting or unusual. Part of that haul was some LaBlue Girl tapes, I’ve watched them and they are indeed fully uncensored. I’m not sure if these tapes are what’s considered lost but, they are in English and I believe they are the first release of this OVA in the West.
I have the boxset of the six VHS series and if memory serves be right, I can someone corroborate the lost media wiki entry regarding censorship. I only say somewhat, I have I never seen any other version and claims about its later censorship are surprising, but understandable.
Yes, the OVA is uncensored - there is no mosiac blurring common in Japanese pornography but what was left is underwhelming. It is apparent the production company used that blurring to hide the fact they would not time or effort in animating something no one was going to see, therefore the scenes that would have blurred appear to be poorly or quickly drawn to only vaguely resemble genitals.
Nin-nin, Miko Mido's lecherous sidekick and comic relief, does appear throughout the series. I am fairly sure they - nin-nin and Miko Mido - never have sex but they are constantly put in incredibly sexual situations as they fight demons.
Thought it is not brought up, the packaging and OVA subtitles declare that Miko is 16 years old.