The SLCC published a list entitled "Wonderland Parish Council" with about 50 policies and other documents a small parish council might be expected to adopt. Needless to say, I doubt whether anybody actually has!
As a starting point, go through your Clerk's contract of employment, which will cross reference numerous other policies and procedures relating to the clerk's employment. Visit the Templates section of the NALC website (login required) or ACAS to find up-to-date templates for each of these policies.
Further policy templates are listed on the NALC page, so pick and choose those most relevant to your operations, some of which will be legal requirements (data protection, management and record-keeping, health and safety etc), so do those first. Add a couple to every agenda and you'll soon be fully compliant.