When do you use "one of the few" and "one of few"?
Take for example:
He went to a boarding school, one of few in the country.
He went to a boarding school, one of the few in the country.
Is there a difference?
We would only use the few when we want a noun phrase which points to a small group (often with a sense of them being an élite, but not necessarily).
We would only use a bare few when pointing out the number but using another noun to show what we are talking about:
We may use the two together for effect:
Here the last few is in this bare use, after two uses of "the few". (On a related, but only slightly on-topic note "The Few" capitalised refers to the pilots of the Battle of Britain).
In the case of your sentences, we have a clause that has a noun pointing out what we are talking about. After that we can either use the bare form and depend upon this noun to let us know what we are talking about, or we can use "the few" form and have that be a noun in that second clause.
So in this case, both are valid, and the meaning is the same, though arrived at in a slightly different way. All the sentences I give here use few and the few in ways that are outside of this overlap and couldn't have any of the uses switched.