Hi Cara,
I have tried finding the Marriage with all the resources I have with no luck sorry.
I found them in 1841 under Comack

Hopefully someone else can come up with something for you before you purchase another Cert. Unfortunately that may be your only option.
Personally I would be complaining about the Cert you have and asking for another copy!
I even tried looking in Ireland for a Marriage even though Ann was from Essex. It is possible she was from a Military Family.
IGI has one 1823 to Annam CURRIGAN.
(Just a stab in the dark and not really likely though)
Trish
