Wouldn't it be easier to take a price list from the lords trade show in sept and see what the cost price is for a bat with a rrp of £200+. Add on 20% VAT and the remainder is margin less expenses. As Buzz said, it's not easy for a retailer to stock a G1+ bat for £200 and don't forget you are getting the luxury of trying each bat out on the premises. If you buy direct or online that's not an option.
Hypothetical example, but realistic one:
Trade price = £55
Add VAT at 20% = £66
RRP = £100 (cannot sell at full RRP)
Selling price = £80 (20% discount = competitive)
Gross profit = £14 if not VAT registered (if VAT registered, this drops to £11.67)
Post out for £6 charge to customer, courier cost £9. Now profit = £11
Take away premises rent, rates, electricity, staff, insurance, royalties for playing the radio, and other things = not worth getting out of bed for