I work in the podiatry department of an NHS trust. My advice would be to get yourself referred to the podiatry service. GPs can only do so much but a biomechanic podiatrist will be able to look into arch supports and other orthotics as well as podiatric surgery if the pain hasn't eased in a year or so.
To be referred you'd need your GP to send your details to the podiatry department or, if they won't, you can self-refer (to the Trust I work in anyway) but this is not the recommended route. In my Trust you'd probably have to go to a talk with a number of other PF sufferers and then decide on a course of action afterward.
Good luck!