Very good question - with all accessories, I am not sure. I saw one sell in the US with just the bayonet for $2,300 (£1,800). For my condition rifle, with the magazine matching, the last I saw sell for £1,350 a few months ago. Highwood Classic Arms sold one the same as mine with a mismatched mag for £1,200 recently. Mummified rifles are around £3k (one sold on SD for £3k a few months ago link), depending where and if you can find them.
If I had to take a guess, I'd say with all matching accessories in unissued condition - £1,500 - £1,800?