Newton Comics' The Avengers #10 was published 15 November 1975:
The cover was originally published on Marvel Comics' The Avengers #11:
Newton also printed this cover as a poster:
The story contents are as follows:
[The Mighty Avengers Meet] Spider-Man!, originally published in The Avengers #11, December 1964
Somewhere Lurks The Phantom!, originally published in Tales of Suspense #63, March 1965
The title to the first story was shortened due to the cropping at the top of the splash page. This was done to accommodate the indicia at the bottom of the page. Here's a scan of the splash page in the Newton edition:
This is a scan of the original page as it appears in my copy of Marvel Masterworks Vol. 9 The Avengers Nos. 11-20, 1989 [First Printing]:
Only the first six pages of Somewhere Lurks the Phantom! are reprinted in this issue. It continues next issue. It is otherwise unmodified.
Newton Comics' The Avengers #10 skipped Marvel Comics' The Avengers #10 so they were once again out of sync.
The poster in the is issue is The Avengers:
This previously appeared on the cover of The Avengers #6.
This issue contains in-house advertisements for The X-Men and The Avengers #2:
and Giant Team-Up Annual #1:
The subscription page has The Silver Surfer and The X-Men added to the roster.
The contest expires 29 December 1975.