Personally as an Airsporter collector, I think it is £50 over priced for a dealer, but considering which model it is, MK2 concealed lever S (probably the prettiest after a late S carbine)(I dont go mad for Stutzens for some reason).... I dont think its as far over the top as some are saying.
It is in a quite nicely figured walnut stock which is pretty unusual for an S.
Privately I would be happy to pay £275 for that and maybe £325 in a dealers if I really wanted it. Pickering is a lovely shop and friendly and I am sure if you walked in with cash a deal could be done, but they will price it with a PX in ind so maybe thats not an outright sale price?

The best shooting models for accurate shooting are late mk2 with dovetails and a late rotary breech model.
I have a soft spot for 1980's S models and 1950's Mk1's, especially clubs, but I struggle with open sights now.

If you need an accurate vermin tool buy a TX200 or Pro sport.