Fortified bridges were a real thing and lots of people built them; I don’t know that they particularly distinguish one noble house as an analogue to the Freys, necessarily.

Rather, I think the correct analogue to the “Late Lord” Walder Frey is the perfidious Thomas Stanley:
”Lord Stanley…came from a staunch Lancastrian House, but was married into the Yorkists through the Earl of Warwick. At the Battle of Blore Heath, one of the opening battles of the war, Stanley raised 2,000 men at his King’s command but then withheld them just a few miles away as a Lancastrian army was defeated by a smaller Yorkist force. When Edward IV took up the Yorkist cause, Stanley defected and fought alongside the new King; when Warwick defected from Edward IV, Stanley fought to restore Henry VI for the last time. Remarkably, he managed to get appointed to Edward IV’s royal council even after his betrayal. He then married Margaret Beaufort, the mother of Henry Tudor, while helping Richard III fight the Scots. Famously, Stanley held back his forces at Bosworth Field despite Richard III holding his son hostage, and then charged Richard’s rear once the King was fully committed, personally crowning Henry VII to make sure he ended up on the right side.”
As his reward for conspicuous disloyalty to both sides and general amorality (Stanley is one of the candidates for having actually killed the Princes in the Tower), Stanley was raised from a baroncy to the Earldom of Derby, was made a knight of the Garter, Lord High Constable of England, High Steward of the Duchy of Lancaster, Chamberlain of Chester and North Wales, and many many other honors, offices, and lands.

And what makes it worse is that, as his family prospered quite well under the Tudors, his descendants were patrons of William Shakespeare, who made Stanley out to be a righteous and loyal vassal in his plays. Just goes to show that it really doesn’t matter who writes the histories as much as who pays for the histories to be written.