Interestingly, they also appear to sell the microprocessor by itself, along with recommendations of what memory and resonator to purchase. So you really can build it ALL yourself if you really felt like it.
That is really cool! I am a huge arduino and RPi geek and love messing around with microcontrollers. I have never looked at BASIC stamp, but it looks pretty cool! I think that the marriage of electronics, microcontrollers and programming is the cat's meow!