Johnnie Walker 150th Anniversary

[fr1day]

Hi folks, I have an opportunity to purchase a bottle of JW 150th Anniversary (see attached pic) and was looking for some advice as to what kind of demand there is for these bottlings, and roughly what price would it fetch if wanted to sell it on?

Item 84-3.jpg

I see that The Whisky Exchange have a bottle listed at £1,500 - obviously this is retail pricing. What would be a fair price in a private sale or auction?

Thanks in advance,
Mark.