Here's the link to the online GRO site for certificate ordering:
www.gro.gov.uk/gro/content/certificates/There is a part of the form where you can ask them to check references, and they say that if you have done your own searching in the GRO indexes and have found more than one reference to the name you are researching, or are unsure which is the entry you require, they offer reference checking online. The charge is £7 for action on the first entry, which includes the cost of the certificate, and £3 for checking each subsequent reference against the information you have provided. You must give one piece of information that you are sure will appear on the certificate, in your case the father's name. A certificate will only be issued if the entry matches the checking point you give them.
So in other words, if it's the wrong one they keep £3
Or, you could apply direct to the local register office, where, if you're lucky as I have been mostly, they will check for nothing!
You could do the same for the Eliza Boxall marriage, stipulating Henry's father's name and occupation perhaps.
Link to list of register offices:
http://www.ukbmd.org.uk/genuki/reg/regoff.htmlBarbara
sorry Mum44 for duplicating some info