A quick spin through the Republic turned up dozens of passages in which Plato either ascribes virtue to non-philosophers or says things that imply that they have virtue.
An anonymous commentator (rightly, in my view) drew attention to important passages in book 4.
But here are some examples from other books:
1.353d--(An obvious point, but perhaps worth making nonetheless) The Function Argument presupposes that justice in the ordinary sense, as meant by the interlocutors of the dialogue at that point, is the virtue of the soul.
3.390d --Odysseus' "Bear up, my heart" is cited as an example of genuine endurance and self-mastery. (This is one among many such examples in books 2 and 3.)
3.395c--Socrates insist that, from earliest childhood, children should be given appropriate models in story of bravery, self-discipline, piety, and liberality. But these won't be stories about 'philosophers'!
6.500d--"So the philosopher, spending his time with what is divine and ordered, in fact becomes as ordered and divine as it is possible for a human being to be. ...And if there were some compulsion on him to put what he sees there into effect in human behavior, both in private and public, instead of simply moulding his own personality, do you think there will be anything wrong with him as the craftsman of the self-discipline, justice, and general excellence we need in the ordinary population (sumpa/shj th=j dhmotikh=j a)reth=j)?" (This translation and others are Tom Griffith's. It's not a translation that helps Bobonich, but it's not obviously wrong.)
6.505e--"This is what every soul follows (o(\ dh\ diw/kei me\n a(/pasa yuxh/). All its actions are directed at [the good]. It has a sort of divine intuition that the good is something, but it is in doubt, unable to get a firm grasp on what it is, or find any firm belief of the kind it has about other things." Note here: 'every soul' . Note Plato's willingness to identify what souls are striving for without their knowing it.
book 8--The descriptions of characters corresponding to kinds of constitution are apparently meant to form a sequence from ideally good to ideally bad, implying degrees of virtue and virtues among non-philosophers:
e.g. "And the higher the value they put on [making money], the lower the value they would put on virtue" (550e) implies variations in degree of virtue.9. 580c--"The best and most just character is the happiest. This is the one who is the most kingly, the one who is king over himself. The worst and most unjust is the unhappiest..."
e.g. "Well, it's the next best after the first one I mentioned. And it does compel the citizens to pay some regard to virtue" (556a), which implies that a general concern for virtue is the criterion of the goodness of a constitution.
9. 589d--"Praiseworthy actions are what bring the savage elements of our nature under the control of the human--or rather, perhaps, of the divine--while shameful actions are what makes the gentle element a slave to the fierce." But that actions are praiseworthy or shameful (here kala\ kai\ ai)sxra//\) can be recognized by other people generally, on ordinary and accessible grounds.
Here's a passage which would be hard to differentiate from the outlook of the Laws:
9.590d--"It's just that it's better for everyone to be ruled by what is divine and wise. Ideally he will have his own divine and wise element within himself, but failing that it will be imposed on him from the outside, so that as far as possible we may all be equal, and all friends, since we are all under the guidance of the same commander.....[This] is clearly the aim ...both of the laws, which is the ally of all the inhabitants of the city, and of our own government of our children."
Here's a passage in which 'love of wisdom' is clearly meant in the broad sense; it is said to be a characteristic of soul generally:
10.611e (at the conclusion of the argument for immortality)--"We should look to the soul's love of wisdom (ei)j th\n filosofi/an au)th=j). We should bear in mind what it clings to, the kind of company it yearns for, since it is kin to that which is divine, immortal and always existing, and what it could become if it devoted itself entirely to this..."
Here is yet another passage that clearly recognizes virtue and vice as ideals and allows for degrees in between:
10.618e--"...defining the worse and the better life with reference to the nature of the soul, calling that worse which leads the soul along the road to greater injustice, and that better which leads along the road to greater justice."