According to Family Search the only place with the images for Little Stanmore online is Ancestry. https://www.familysearch.org/wiki/en/Little_Stanmore,_Middlesex_Genealogy
Unfortunately something has gone wrong there and one can't load the images of the earlier registers (very odd you can see the thumbnails of each page but when you try to view it, you get a much more modern register .The index doesn't help... lots of odd transcriptions in the earlier registers.)
Although I can't view it, I can see the citation for the register
London Metropolitan Archives; London, England; Church of England Parish Registers, 1538-1812; Reference Number: DRO/109/00, 1558-1680
I would normally add the name of the parish after the ref number and if poss the image no. Then add image viewed on ancestry.co.uk I don't link in any case because I get fed up with links that go to ancestry.com which 9 times out of 10 don't work for me.
Most times, especially with the earlier records I put a full transcription of the entry. But even without it someone should be able to find the entry if they had access to the register.