Here's examples of the type of person that would be suitable:
accountant
airline pilot
articled clerk of a limited company
assurance agent of recognised company
bank/building society official
barrister
chairman/director of limited company
chiropodist
commissioner of oaths
councillor (local or county)
civil servant (permanent), but not someone who works for IPS
dentist
director/manager of a VAT-registered charity
director/manager/personnel officer of a VAT-registered company
engineer (with professional qualifications)
financial services intermediary (eg a stockbroker or insurance broker)
fire service official
funeral director
insurance agent (full time) of a recognised company
journalist
Justice of the Peace
legal secretary (fellow or associate member of the Institute of Legal Secretaries and PAs)
licensee of public house
local government officer
manager/personnel officer (of a limited company)
member, associate or fellow of a professional body
Member of Parliament
Merchant Navy officer
minister of a recognised religion (including Christian Science)
nurse (RGN and RMN)
officer of the armed services (active or retired)
optician
paralegal (certified paralegal, qualified paralegal or associate member of the Institute of Paralegals)
person with honours (an OBE or MBE, for example)
pharmacist
photographer (professional)
police officer
Post Office official
president/secretary of a recognised organisation
Salvation Army officer
social worker
solicitor
surveyor
teacher, lecturer
trade union officer
travel agent (qualified)
valuer or auctioneer (fellows and associate members of the incorporated society)
Warrant Officers and Chief Petty Officers