Forgive me for my language, but could you please tell me which one is grammatically correct:

Those son's/sons of bitches.


anonymousson's/sons of

Consider that possessives occur before nouns, not before prepositions, and you can answer this yourself.

Paul's of friends? Never.



only #2

Many people who swear tend not to fret too much about grammar.

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In the US you'd hear: "Those son of a b_tches." Putting in the complete plural is too awkward.

 CalifJim's reply was promoted to an answer.
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