But still I do find the scarcity of information again, as I can't find any information regarding Rolex Precision models here, not mention the specs to validate the genuineness of particular ref model. Is there a place to find more holistic and detailed information?
"Precision" was kind of a catch-all phrase used by Rolex for watches with non-chronometer rated movements. Some were automatic, some manual wind. Some had Oyster cases, some were not waterproof. Some had Swiss made cases, some had locally made cases with Rolex movements.
I don't know of any website that details all of the different Rolex models. There is a pretty good forum dedicated to vintage Rolex watches in general:http://www.vintagerolexforum.com/
There are very knowledgeable people there. However, since these models are not as collectible as other (particularly the GMT and Submariner) Rolex time-only models, there isn't that much information on the Precision line.
Hope this helps,