You can search the partial GRO index which is still being transcribed and by no means finished yet at http://www.freebmd.org.uk/ for free.
If you live in the UK, you can search the full GRO indexes for free at your local main reference library - or at your nearest LDS family history centre.
The full GRO index is also online and can be searched for a small fee at www.1837online.com There is also the IGI which is free to search at www.familysearch.org
I don't know if you now have this information so, if not, the marriage can probably be narrowed down to All Saints church in Maidstone - at least I think that's the church which the ref. C35 Maidstone represents on the Kent Registration Services site http://extranet3.kent.gov.uk/sp/rois/marriagesearch.cfm