Non-settei reproduction sketches?

I've noticed a few of these Sailor Moon repro sketch sets.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280075285956
I'm fundamentally uninterested in the series, but what is this? The seller is generally accurate in identification and lists this as official. Many of the sketches are also in color which implies they're not xeroxes used in production, which have always been in black and white in my experience. What are the hallmarks of this type of thing so that they can be identified by a buyer when someone unknowingly or unscrupulously doesn't list them as repros?

The only thing I can key in on is the red stamped bits on the one sketch.
I have one similar from Hana Yori Dango:
http://aernath.rubberslug.com/gallery/inv_info.asp?ItemID=101780
Where the stamp is who the character is: Rui
And what his clothes are: Cosume 9A

And one other from Marmalade Boy:
http://www.rubberslug.com/user/73419dcd00864899b8c675b3e18a19c8/298980-3002675-Yuu%20B9%20genga.JPG
Where the stamp is to make the back black, shown here:
http://www.rubberslug.com/user/73419dcd00864899b8c675b3e18a19c8/298979-6990572-Yuu%20B9%20back.JPG

Other than that?
I dunno. ^_^

They are official sketch copies released by Toei in booklets. I'm pretty sure there was some discussion about these over on Anime-Beta...maybe I'll see if I can dig up any links...

Edit:
http://www.anime-beta.com/phpBB/viewtopic.php?t=19927

So, it seems unique to Sailor Moon. No one in the Beta thread actually confirmed these were from the mentioned book (and if the lines are fady, as mentioned in the thread, that also seems kinda unlikely); if anyone can confirm tat they are from the mentioned book, feel free to mention it here...

Not really what you were asking, but I thought I'd throw my 2 cents in anyways. I know that there are 2 cel reproduction books *somewhere between 40-60 pages each* for the first season. One seeming to deal with the first ark up until she finds out she's a princess, and one after that. There also seem to be two different ones for the R season. One has a group picture of the main characters on front (although I could be mistaking this from the first season) including Umino. The second is one with Usagi and chibiusa sprawled out on a bed.

Typically, these are bound at the top, are the size of a normal genga/douga sheet, have colored lines (like genga), and carry the silver toei sticker on the bottom corner (usually).

Other than that, I have seen one once avalible for the S season (or someone went out of their way to make one), and I've seen one for the Stars season listed a total of 3 times -twice on japanese auction sites, and once on Ebay. This is the only one that I own out of the ones I mentioned previously. I do not know if there was more than one produced for the S or Stars seasons (like with the first two), or if any were produced for the SuperS season. Though, it seems like a logical conclusion that it probably was.

If I remember correctly, the pages are not punched at the top like typical genga/dougas would be. I'd have to check with the one I own to be sure.