Newton Comics' The Amazing Spider-Man #14 was published 6 December 1975:
The cover is from Marvel's The Amazing Spider-Man #13:
The story contents are as follows:
The Menace of... Mysterio!, originally published in The Amazing Spider-Man #13, June 1964
Challenged by The Human Cobra!, originally published in Journey into Mystery #98, November 1963
The splash page to The Menace of... Mysterio! has been cropped at the bottom to accommodate the indicia:
The previous owner of this copy used the white space to note the Dr. Strange poster and the original printing of the story. This kid loved his comics. Good stuff!
Only the first seven pages of the Thor story are reprinted in this issue. The reader is advised it is to be continued, but it does not appear in The Amazing Spider-Man #15.
The Doctor Strange poster is from Newton's Doctor Strange #6:
The scan is not very clear but it appears to be missing the cover date.
The expiry date for the contest is 19 January 1976.