A verbal agreement is still an agreement. They didn't ask for a deposit so they didn't have any right to go and sell them out from beneath you. If they were going to back out of the deal they should have not given any kind of verbal agreements or impressions otherwise, that displays incredibly poor business ethics. You aren't going to do anything for a reputation, and definitely not going to get any repeat customers, doing business that way.
As for London Reptiles, the location listed is only minutes from me, and it is a small city, but I have never heard of them, only seen their ad on kingsnake. From what I read in this thread though I woudl certainly be hesitant to do business with them......