We have been informed that the scanning of images is complete, and the scanned images are being assessed by an expert at the Sri Jayawardhanapura Uni. I am hoping to speak with him this week. The stumbling block is that we have not been given the actual images, it seems no-one wants to make a decision. Optimistically, we can start the transcription at any time. Once the images are available I intend to visit Colombo once more to get the transcription going.
There are, I believe printed editions, and the text, which is not necessarily identical with the printed edition, is inscribed in stone at the Kuthodaw Pagoda.
It’s the earliest that I know of, there may well be others.
All modern editions and translations are based on various manuscripts of the 18th and 19th centuries, which were edited and published in modern times. The differences between editions are minimal. If you look, for example, at Bhikkhu Bodhi’s footnotes, he frequently discusses different readings and other variations between editions.