I have a little information about your Rees Price. He appears on the 1851 Census in Velindre at 91 yrs of age and died at 93 yrs in 1852, buried in Glasbury. That would put his birth at about 1760. The 1851 Census says he was born in Bronllys but I have not found a record of that. The Glasbury Vestry Minutes say he was a tailor.
Now, the reason why I am interested in him is the possibility that the could be the father of my illegitimate ancestor, and direct-paternal-line surname originator, John Vaughan, christened 1789 in neighboring Hay. The mother was Hannah or Joanna Vaughan (1763-after 1797) daughter of Roger and Elizabeth Vaughan of Glasbury. I have info from the Hay Vestry Minutes that Roger Vaughan petitioned for assistance in caring for his daughter's illegitimate son "on behalf of the tailor who is in gaol." I have not confirmed this is Rees Price, tailor of Glasbury, but the circumstantial evidence is there and I am trying to find something more solid. So, I could be your distant, illegitimate cousin, so to speak. But I'm happy to be a Vaughn not a Price, if that's OK.
If you wish to communicate with me directly, I am glad to share the specific documentation I have. you can e-mail at grant[.]vaughn[at]gmail[.]com.