I am a divorced Roman Catholic. I did not seek an annulment after my divorce 10 years ago and am now planning to remarry a non catholic. We attend a non denominational church and and both consider ourselves "religious" people. Because of not having an annulment, I understand we cannot be married within the catholic church. However, I am wondering whether a "retired" or "active" catholic priest could officiate at our civil wedding ceremony? Thanks.
Not if you want it to be a valid marriage. Being married outside of canonical form renders an attempted marriage of a Catholic invalid. Catholic priests may not officiate at any wedding that the Church considers invalid. If he does so it would be considered a serious offense by his bishop.
While retired priests are not active in an assignment they are still priests of the Church and are expected to follow the canons of the Church.