I just got this today for $0.25 at the local library sale
I think its a magazine (although the paper is tougher then a magazine, almost cardboard-ish). It seems to be complete (I only took a few pics, I didn't photograph the whole thing but there is more to it then what I show). All the pages inside are two page pics, and they all match. Only the front cover and back cover don't seem to make one pic, although looking at the spine it doesn't look like anything has fallen/been ripped off.
The pics don't really show how, while the edges of the page have normal wear, the images are all very crisp. Its in good condition for something that I'm assuming is about 30 or so years old (it doesn't look like its a reprint or anything, although if there is a specific date I can't tell because its all in japanese). It looks like its introducing/showing off Flashman, so I'm assuming it came out around the time the show did.
I have no idea how this thing lasted 30 years and then ended up mixed into a bunch of bargain kids books at a public library sale in a small town in the US, but its one of the coolest things I've found at the monthly library sale, and definitely the most surprising. I only knew it was there because I heard a young kid say
"Oh, look, Power Rangers! Aw, I can't get it. Its not in English".
He walked away, and I was intrigued by what I heard so I went over and found this. I never would have thought to look in the pile of little kids books. So, a cool little discovery.