Smrobs is for sure right about getting a registered mare for breeding. I do not know what your plans for the foal are, but a registered foal will ALWAYS trump a grade foal in a sale. There are just too many grade horses, and irresponsible breeding is what gives us those flaws like long pasterns, etc.
Maura also brings up an interesting point. A horse that will be safe/beginner friendly AND suitable for breeding's going to come with a price tag.
If you're not even sure about your breeding plan, I'd say hold on, and maybe search for a mare or gelding that will teach you, and suit your immediate needs. Should you decide to breed later on, look for a good broodmare when you know a little more about breeding and conformation.
And Smrobs is right, fee free to post other possible buys. :]