I think this might be him
From http://www.peoplescollection.wales/content/branas-ucha-–-house-history
Gruffudd ap Rhys (son of Rhys ap Ieuan). Gruffydd was Lord of Crogen and Branas Uchaf. He was born about 1400
Rheinallt ap Gruffudd (son of Gruffudd ap Rhys). He was born about 1430
Therefore his wife was Lowry (havent found her parents yet.
I'm suspecting Lowry's parents are not known. How she has a brother Ieuan Gwyn (John Prys) ...his parents don't make sense.
There are sons missing from the union of Lowry & Reinallt ap Gruffydd
From https://keeganfamilytree.wordpress.com/2014/01/08/owain-brogyntyn/
Their son, Rhys ab Ieuan became fourth lord of Cymer and Baron of Crogen and Branas. His son Gruffydd ap Rhys inherited both Crogen and Branas, but he split this inheritance between two of his sons, Hywel and Rheinallt, with Hywel getting Crogen and Rheinallt getting Branas. This Rheinallt ap Gruffydd now has just Branas and has five sons. From the records it appears that his third son, Robert inherited Branas. This Robert then built the hall house of Branas Ucha in 1508-9.
One of the connections on the histories here isn't making sense -- Margred verch Ieuan, daughter of Ieuan ap Llewellyn ap Dafydd ap Gruffydd ab Owain Brogyntyn, marries Rhys ap Llewellyn. Fair enough, but then their son is called Rhys ab Ieuan. Instead of Rhys ap Rhys.
I haven't yet found a clear way to connect this bit of the tree to the Owain Brogyntyn line.
But. Let's disconnect Lowri and her brother from their parents -- to whom they belong I do not know, but they're not making sense there.
Bingo
http://wc.rootsweb.ancestry.com/cgi-bin/igm.cgi?op=GET&db=john_...
(John Newport does a nice job)
"Heraldic Visitations of Wales and Part of the Marches; between the years 1586 and 1613", under the authority of Clarencieux and Norroy, two Kings at Arms, by Lewys Dwnn, Deputy Herald at Arms. Page: Vol. I, pg 252
... And here's our Virginia immigrant
http://wc.rootsweb.ancestry.com/cgi-bin/igm.cgi?op=GET&db=john%...
This is pretty stinky John Price, Ancient Planter I added to the http://www.geni.com/projects/Check-Me/30217 project