If you are looking for a cheap playing ruleset - the early rulebook has a fun and simple feel to it - and Call of Cthulhu rules haven't changed dramatically in 20+ years. $3.50 for something which can give you and your friends weeks of gaming fun reminds me just how cheap our hobby can be (the gaming that is, not the collecting

)
Personally I prefer the 3rd Ed UK box set.
By comparison, here is a recently finished rulebook (updated rules, better artwork and layout), which was a good price.
** expired/removed eBay auction **And someone here just
had to have the
OOP Orient Express set...
** expired/removed eBay auction **C'mon Chaosium, get with the re-print!!