looks gorgeous mate

as you probably know it can be very difficult to value cossies, but in that condition i reckon anywhere between £7k and £8.5k. reckon if it was totally standard you might even get more for it!
but you do see such a variance on the quality of saffs and their prices ( you can pick a half decent one for about 4.5k, a runner for £3k and 'almost minters' for about £6k. from the pictures yours looks pretty special so i reckon £8k is about right.
of course thats just an opinion so if you personally value it higher then tell me to sling it