Doesnt look too bad, a mate of mine does PDR (paintless dent repair) and they charge £50 a panel, i would say you shouldnt pay more than £100 tops, will ask him to have a look at the pic to see what he thinks
i doubt a cosmetic repair as in dent man would make that look great, i'm a panel beater and it would be a fairly easy repair and shouldt cost 2 much but obviously atleast the 1/4 panel will nee apinting. i'm located in derby incase your close this way and wanted it doing at a nice low club price.