Yikes! I've hit a real road block.
7Dn I had this as moving the appropriate letter from the first word to the third, making it an anagram of the second minus its third letter, giving Judith Durham possibly. However, if I'm right about 1 across, which I have as a word which sounds like another 60s band, and about 3 down, which I have as a word which rhymes with a band featuring Peter Frampton, but starting with S, then my first letter of 7 Down must be M, O or T. And anyway is "FINDER" really a definition of an anagram of the second word without the money? I hope I'm being appropriately convoluted, but fear this may result in readers of this thread being completely unable to work out what I'm on about. I need to know if 7 down could be Bruce Woodley or JD.