I think the closed question, “'These sort of things': is it grammatical? (2,670,000 hits on Google)” should be reopened.
As Peter Shor said,
Except that it's not an exact duplicate. This question deals with "these kind of X", with a plural determinant and a singular word from kind/type/sort, and those questions deal with "this kind" or "these kinds". –
Furthermore, this particular question has one good answer citing a good reference that, in my opinion, everyone should read, but a lot of people, probably, wont read it if the etiquette [closed] appears.
Thank you.