Yup; there are a handful of those in Song of Ice & Fire canon: the Conningtons, the Lorches, the Kettleblacks. I seem to remember either the Cassells or the Pooles (don't remember which off-hand) were as well.
More relevantly, there are knightly Houses in the rule set for Song of Ice & Fire.
Developer, Song of Ice & Fire
Green Ronin Publishing
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