Newton Comics' The Silver Surfer #4 is cover-dated December 1975:
The cover is from Marvel Comics' The Silver Surfer #4:
The story in this issue is The Good, the Bad, and the Uncanny! originally published in The Silver Surfer #4. This was subsequently recycled by Newton Comics in Newton Holiday Spectacular.
This issue includes the following poster:
This poster is from the cover of The Amazing Spider-Man #134.
This issue was advertised in-house, including in this issue:
An earlier version of this advertisement was included The Avengers Giant Size 84 Page Annual #1 with the added tag Out Next Week:
The Fantastic Four #12
This issue contains the Captain America Bulletin page:
As discussed previously, the Marvel Mailbag pages referred to in this advertisement announced the forthcoming monthly titles and 52-page titles. Of course The Silver Surfer was a 52-page monthly title since inception, but it does explain the New Giant Size Monthly Edition banner on the cover.
This issue also includes a t-shirt offer and a contest with the expiry date 31 January 1976.
As per The Silver Surfer #3, there is conflicting information regarding the publication date of this issue.
The indicia in this issue has the following date information: Vol-1 No-4 Dec 1975 issue - which, in this case conforms to the cover date.
However, this issue was advertised as Out Now in the Sunday Observer 23 November 1975:
Like the ad featuring The Avengers Giant 84 Page Annual #1, this ad was issued prematurely, and is symptomatic of the disorganisation and changes afoot in the Newton office around this time.
I date this issue to 20 December 1975 on the basis of the cover date, indicia date, the in-house advertisement in The Avengers Giant Sie 84 Page Annual #1, the established monthly schedule, and the contest expiry date which conforms to other issues with the same expiry date issued 20 December 1975.