I am 100% sure that this single came with the sleeve that is called MGM Records (version 1) in the sleeve guide. The guy that sold me a copy of this pressing found a box full of them from a ex-records shop stock and they all had that sleeve. Go to US MGM/Verve factory sleeves (1966-68) to see pictures of it.
Alan Mansfield has a copy of this single with the b-side label on both sides. Here is what he wrote me:
“You may be interested to hear and report to zappafrenzy people, that I have just acquired a copy of Verve Records VK-10418 USA (version 4) which has the same ‘Help I’m A Rock’ label pasted on both sides – the matrix numbers suggest that the recordings on each side are different i.e. How Could I Be Such A Fool + Help I’m A Rock: It Can’t Happen Here – it’s just that they both bear the same label. It came in an ‘MGM Records Version 1’ factory sleeve.”
“I also own a quiet rare Verve white label test pressing of “It Can’t Happen Here” dated June 23rd, 1966 (see scans): This promo pre-dates the stock and promo copies of the first officially released 2-sided Mothers Of Invention single which shares the same catalog number VK-I0418. VK-I0418 and 100526-1 are etched into the runoff wax on the A-side, and the B-side (which is blank) has the initials “CG” in pen on a completely white label and EXP-1-110-L.P.D. etched into the runoff wax.”