Usually when a church register mentions a licence it's referring to one issued by the church authorities. See
http://www.yourchurchwedding.org/youre-welcome/do-we-need-a-marriage-licence.aspx for more on these - although this describes the current situation, I think it would have been more or less the same in 1954, particularly as regards Special and Common Licences.
The first place to ask about records of the issue of Common Licences would be the diocesan record office - in this case the Essex Record Office, which holds records for the Diocese of Chelmsford. It would also be possible for any papers which were retained in the parish to have made their way to the record office at some point, so you could ask them to check this as well. (There may be an online catalogue - it's not one of my counties of interest, though, so I'm not sure.)
If it was a Special Licence (much less common), there may be records at the Faculty Office in Westminster, or else they might be able to advise further - contact details on the site I linked to. Again, there's a chance something might have been kept in the parish and deposited at the record office.
Hope this helps,
Arthur
