Need advice on diamond ring.

I have a gold and 5 diamond ring that was my grandmother's, she had to have it cut off to remove from finger and I have had it in a jewelry box for about 20 years now. Ring was made in the 1970s or very early 80s, The Diamonds are real, one was replaced about 30 years ago and my grandfather paid $1,000 for the replacement diamond. Now I am thinking about selling the ring, not sure best way. Could remove diamonds and get appraisal or fix ring cut area and sell as whole ring. I have no idea on value, I would think its worth a minimum of $3,000 but that's just a guess, any info is appreciated.