Comics are an excellent source of information about old cereal promotions and so it is with the Luminous Spooks. The following image is from TV Century 21 comic for the week ending 21st August 1965 (actually dated 2065, this being an imagined newspaper from the future!). I received it from Kim Stevens soon after blogging an appeal for information about the Spooks many years ago.
There was a wealth of information here for me to rediscover or to confirm: the year (and month) of the promotion (not 1967, as I'd guessed), the cereal (I had been pretty sure it was Sugar Puffs), that there was a 'spooky story' contest (not remembered at all), the number and types of Spook (actually seared into my memory), the 3D Haunted Manor (likewise) and that all the Spooks have names - even the clock (I knew just the names Tilly and Winnie).
An almost identical advertisement is shown in this high resolution scan on flickr (user combophoto). A close comparison of these scans reveals subtle differences in the shading in the artwork, as well as in the layout and typeface of the text. Although there are no details on the page, it's from Valiant comic, week ending 21 August 1965, which I have seen. (You can just make out evidence of a comic strip - Jack O'Justice - on the other side of the page of that issue, e.g. speech bubbles that are just visible around the turrets of the castle).
Another example turned up on eBay in March 2018 (seller triciaizzynpete seems to specialize in chopping up old comics and magazines for the ads - tut-tut). It's from The Victor comic, exact date unknown, and appears to be identical to the one in Valiant:
TV Century 21 was a large comic, whereas Valiant and The Victor were standard-sized, so this may account for the differences between the adverts (photographic enlargement or reduction perhaps not being suitable?).
Using information supplied by Kim, based on comic adverts, the Sugar Puffs promotions from the Fish to the Spooks were as follows:
May 1964 Luminous Fish
July 1964 Jet-crew training contest
August 1964 Roman Gladiators
September 1964 Win a puppy or pony
March 1965 Scale Model Sports Car (8 models to collect)
May 1965 Super TWA Airliner (4 models to collect)
June 1965 Tiddlywinks set (Steve L. remembers these appearing after the Luminous Spooks. Old stock, or perhaps the promotion was resumed?)
August 1965 Luminous Spooks
These promotions really were short-lived, no more than two months, it seems. No wonder I managed to get only a few of the Spooks!
Are there examples in other comics?
Could there be ones with different content, e.g. with pictures of the actual Spooks, cereal packet or even of the TV ad? I suspect this was not the case, unfortunately, as we now have 3 examples, from different publishers, which are basically the same.
I've documented progress so far in the table below. I've excluded comics aimed at teenage girls (were any aimed at teenage boys?) and those aimed at the very young, because those seem much less likely to have run the advert. For now, I think the focus should be on the weeks ending 14, 21, 28 August 1965. Checking September editions could still be useful, but perhaps at another time. Of course, the absence of an advert in one week does not mean it wasn't carried in another. Different submission deadlines and the availability of space would dictate when ads could appear. While there are a lot of titles to check, I suspect that comics from the same publisher would have had the same advert and so of particular interest now are TV Comic and Wham, as these are from publishers where we have no examples so far.
Comic titles compiled with help from 26Pigs.com and wikipedia.
Note:
I've discovered that Ranger comic only started being published the week ending 18 September 1965, so it has now been removed from this list.
Editions from August to early December of Treasure, a comic aimed at young children, have been checked by Peter Watson. The advert was not found, possibly because it had too young a target readership. It and similar comics have been excluded from the list above for this reason.