I read this earlier today and have been thinking about it. I think that as Minimoo said, your committment to a second dog is paramount but from your post I don't doubt that you have that.
Taking on any rescue dog can be difficult, especially for the first few months as they settle in. Having shared our home with 8 (now 6) rescue dogs over the last 5 or so years, I can honestly say that for the first few weeks, for most of them, I spend a lot of the time thinking 'oh my goodness, what have I done?!' That said, I've also been involved in a lot of homechecks and assessments for nessr and if I'm honest, I'm not sure that this sounds like the best match to me.
Taking on a kennelled dog to live in a home environment isn't impossible, but is hard work. Living above your pub won't make it any harder than if you lived, say, in a block of flats, but you will need to be certain that you can manage the toilet training ie taking him outside every half an hour and praising him like mad if he does a wee or poo but ignoring it if he has an accident in your house. Our first dog, Benjy, was a 10ish year old ex working dog. The first thing he did when he arrived here was to cock his leg on the sofa. You would need to be prepared for him to be unneutered (unless the rescue lady has organised this).
So, yes it could work, but it will be hard work.
The other option is to take on a different rescue dog who perhaps is more used to living in a home environment and therefore may fit in easier to your home. I think what I'm trying to say is that just because this dog is available and needs a home, it doesn't necessarily mean that he is the best dog for your home (or that your home is the best match for him). I understand fully how you feel having been offered this dog, but there are lots of cocker spaniels in rescue waiting for the right home and although I think you could make things work with this dog, there might well be another dog out there better suited to your home / pub environment.
I hope this helps.
