Do you love the dog? Why do the papers matter unless you are going to either: a) put them in a frame on the wall to admire or b) show/breed the dog. If your desire is choice b, then no matter what, you've got some learning to do regarding pedigrees, structure, genetics, inherited diseases, heath screenings, etc.
I showed dogs for years and right now I have two of my last show dogs with pedigrees back generation after generation. One had a litter brother that was ranked one of the top terriers in the AKC time and time again. I also have the Boston I found wandering the streets. Papers or no, I love them all the same.
Spend enough time showing dogs and somebody is going to sue someone else over something. Most of the time it's throwing good money after bad. I had a friend who sued a breeder for switching dogs and not giving hers back when the breeder took the youngsters to get their ears cropped. My friend had DNA from puppy teeth, etc, etc, and on and on. She spent 13K to get the dog back. 13K, people! That's a lot of dog flesh that can be bought for that kind of money. The dog came from good stock, but the genetics were not irreplaceable by any means.
So, what is your goal? Make them give you what you paid for? You paid for a dog. You feel that you paid for papers? Papers can be forged on a computer, which is what they might do. The litter was probably never registered with the UKC. If it was, then the UKC might have a mechanism for this, but so much depends on the breeder. The AKC would probably tell you to spay/neuter the dog and get and ILP so that you can compete in events other than conformation.
If it's a "principle of the thing" deal, well, in my opinion life is too short to waste time on "papers". But, as usual, you get what you pay for and this opinion is free.
