We have seen high factory spec, desired coloured junk sell for 20k at auction and others that need 10K minimum spent on them sell for close to 50K lately.
Others over this price struggle to sell unless they are close to perfect and top spec. If your photos are current and all the numbers line up I think it looks around 25K roughly.
It is going to be worth more money as a panel van that matches the tags (but it will need to be the correct roof and done well etc). Original paper work help price also.
Windowless turret?