Help estimating partial channel set 1.5 tw diamond band

[Calexand]

My sister's friend offered me her channel set wedding band, which does not fit her anymore. According to our local jeweler and GIA certified gemologist, who took quickly surveyed the band, the 14k white gold band contains 11 diamonds (each roughly .136 carat), 1.5 tcw, SI1-2, I color. The gemologist said that he felt 2k would be a good compromise for us on the diamond band, but I noticed recently that the plating is a little worn on the side with tiny black veins, and one side diamond clearly has a flaw inside. The band has a good sparkly fire once it was cleaned and a good weight overall, but I feel like 2k is still a little too high for a used family ring. It's normally in my nature to bargain, but I had not done the research because I was not even considering channel set bands, so I had initially agreed to the 2k. Comparing some prices online, I now think 1,700 would be a little more fair, but I don't want to lowball her. If she had tried to sell the ring through ebay or another site, I am sure she would have lost some of ring's value to a middleman. What would be a fair price for the band? Your opinions are very much valued!