Respectfully @LandSharksAnonymous (and I use that in the true sense, not the 'pretending not to be rude' sense) the places that I know of that do this are not rip-off versions of puppy farms, and sadly £7k won’t cut it either – and the rest!
There seems to be some general confusion about all of this. I’m sure there are some dodgy places that promise the earth but all of the kennels I know, as a writer on (among other things) gundogs, fieldsports and beyond, do an amazing job with the fully-trained dogs they produce. They’re not runts or ‘defective’. They’re not broken. They’re brand-new puppies, fresh from mum like any other well-bred dogs. They have pet life experience, working life experience, they take turns living in the house so they’re not ‘kennel dogs’, they do real-world socialisation, they go in the car, to the pub, out on shoots, get handled by kids etc etc. At Mordor they film the puppies’ journeys so you can literally see it – on Youtube and on Instagram.
I have been up to Mordor and asked a lot of questions, and I have interviewed owners of Mordor fully-trained dogs too. The dogs adapt super quickly to their new homes, and their owners have life-long support. I’m not doing his PR for him because he definitely does not need that but I do feel obliged to explain the process a bit.
I know someone else not mentioned on @Lougle’s list who does this. She’s a wonderful trainer, she breeds various different gundog breeds from her established lines and has both a fully-trained and a part-trained programme now where you can have a pup from a litter and she keeps it to train until whatever age/level agreed. You get the kind of dog you want from her – you can choose what kind of training they get, and are fully involved with the process along with her. Her dogs are extraordinary and the set-up is lovely.
Would I get a fully-trained one from her or anyone else? No! But that’s not because the dogs I know from these kennels aren’t amazing, it’s just because I enjoy training my dog myself. I'd have one of their pups though, for sure. If I had the money for a Mordor (say) spaniel and I was a shipping magnate or an oil tycoon without much free time to train a dog, I’d get one, sure! But I’m not and I do have time, which is why I have a two-year-old cocker that I’ve trained myself. Is she to the same standard? No, because I’m not a trainer – but she is decent.