I don't know anything about the cost of wild boar in England but I have been going to Croati/Poland/Germany/Czech Republic for the last nine winters, four trips each winter, and pay 1500 Euros, all inclusive, for a five day trip of which three are shooting wild Boar.
I normally shoot an average of three per trip, sometimes more, but very rarely draw a blank (or miss!!)
Bearing in mind my trip includes air fare, full board, local gun/shooting permit and all travel at the other end I reckon it must be better value than can possibly be offered in UK at the moment.