Some of these Reinfeld titles were later combined into a single book,
"The Complete Chess Course from Beginning to Winning Chess, A
Comprehensive Yet Simplified Home Study Chess Course. Eight Books in
One" (1959).
The similarity between this online offer and Reinfeld's books seems
suspiciously more than mere coincidence would warrant. If this online
offer is genuine, and not a spoof, I wonder if the seller is not
offering anything original, but has merely repackaged old Fred. If so,
and these books have not yet passed into the public domain, copyright
violation may have occurred.

Are these Reinfeld books good? If I was to 'improve my chess in 7
days'
I would much rather go to the original source

This website is poorly done. I wasn't quite sure what he is selling.
It looks like some crappy ebook.