Haven't read all the replies but just want to say, 2 dogs are easier than one, but get an older dog not a puppy, because they are bloody hard work.
Pure bred cavaliers are a yummy yummy breed ♥ there are plenty of breeders around, but just make sure you do your homework, because they are still in the process of phasing out heart issues and other problems known to the breed.
I'd suggest getting an ex breeder/show dog.. it may have some health issue which is why it won't be used in the breeding program any longer, but at least you know the breeder is doing the right thing and not using a dog with any signs of health issues.
Miley is 100% healthy so far, but her grandmother was diagnosed with a heart murmur at 6 years old although it was only stage 1, she was dead within 6 months. Miley had already had a litter by then, but as soon as her grandmother died so suddenly like that, the breeder didn't want to take the risk, so stopped breeding her immediately and sold her to me