I just read Lily's story in the RIP thread and I must say my heart goes out to you and your family. There's trully so much love for your little one in your words. I sincerely understand your feelings and I feel it's absolutely legitimate that you should want to get a new lil one as close as her as possible. My first yorkie, Sally, died over six years ago and when some four months later I got Rubi, it was Sally's physical appearance I had in mind. They are in fact so much alike, physically, I mean.
I wish you the best of luck in your search. I think thinking about a new one always help to heal the wounds.