The page range for this quarter is 353-419.
The number you quote is at the end of the range which are typically but not exclusively registrar attended or register office marriages. The first numbers in the range are the Anglican churches, follwed by Quakers, Jewish and then the registrar ones.
Unless you can find a mention of them in a newspaper, birth cert for a child which will contain her maiden name or they have her family members with them in later censuses you'll have to buy the certicate from the GRO.
