Thank you all so much for your comments. I really appreciate you taking the time to share your views with me.
Foster Mum's: Thank heaven for you! You're doing a wonderful service. I would enjoy doing this too, but don't know how I would cope with saying "Bye Bye"- sure I would probably end up with a houseful of beauties.
I would be happy to rescue a cav. I would certainly give him/her lots of love and would feel very rewarded knowing the dog was safe with me.
I will give all your advice much thought and won't rush into anything. It's good to share ideas and make an informed choice.