At the end of the day they are worth what someone is prepared to pay. There has been a slow but steady stream going into private owners hands (ones at Shoreham, Topsham, Corsham and ‘Oxfordshire’ come to mind) plus the one which went to the states.
I know what the Midland Air Museum paid for theirs direct from the MoD and although it was 4 figures it wasnt anywhere near the £10K mark .
That said there is now a finite supply in the short term with the last Shawbury ones off to India, of those left available in the UK the condition is getting worse with each one sold – hence more needs to be spent to make a presentable example.
The JetArt one is probably the most complete example around, but knowing how much is required to buy a HUD, MFU’s and an ejector seat to name but a few parts mising from all those sold off by the MOD, the price this is expected to make is probably not that exteme.
Sadly this out of the reach of all but the most commited collector…