Any vaccine under 8 weeks is, well... not good. And pointless.
Here's some info:
Aimee's Rabies Exemption Law: NEWS FLASH: Dr. Jean Dodds New Vaccination Protocol
The important part to know:
"Puppies receive antibodies through their mother’s milk. This natural protection can last 8-14 weeks. Puppies & kittens should NOT be vaccinated at LESS than 8 weeks. Maternal immunity will neutralize the vaccine and little protection (0-38%) will be produced. Vaccination at 6 weeks will, however, delay the timing of the first highly effective vaccine. Vaccinations given 2 weeks apart suppress rather than stimulate the immune system. A series of vaccinations is given starting at 8 weeks and given 3-4 weeks apart up to 16 weeks of age. Another vaccination given sometime after 6 months of age (usually at 1 year 4 months) will provide lifetime immunity."
That said, there are still a lot of breeders out there who will vaccinate (and vets who are willing to do it) because the vets want $ and the breeders can charge more $ if they say the pup has had vaccines. When in reality, they should be keeping them until a t least 10-12 weeks anyway; but most want them weaned and sold by 8 weeks. Quite sad actually. =/
Also, it may not be on the veterinarian invoice because; if it's actually a good vet who refused to vaccinate at under 8 weeks; the breeders can actually pick up the injection at any Farm & Fleet for $5.99 and do it themselves. Lots of breeders do that just to save the cost of the vet visit. >.<
So, it's possible that he did have his shots if the breeder gave the injections herself. But really, she SHOULDN'T have because as said above it will "delay the timing of the first highly effective vaccine. "