Kay,

I can`t find a marriage entry on the IGI for John and Helena in the Isle of Man or England. I suggest you try the GRO at Southport, see the site http://www.statistics.gov.uk/nsbase/registration/certificates.asp
and ask them to do a search for a marriage entry and obtain a copy of the Certificate of Marriage. If possible look first for an entry in the GRO indexes around the year 1867; these should be available at the larger libraries. This makes the task cheaper and quicker if you can supply a reference for the Southport Office to use.