On the goverhment website for all birth, marriage, death, and census records, http://www.scotlandspeople.gov.uk
there is an entry for the marriage.
1957 GRANT CHARLES MCFARLANE BELLA DARVEL /AYR 603/02 0022
Because it is a modern record it cannot be viewed or downloaded. You must press the ORDER button at the end of the index line. This site does charge for the records, but the costs are very reasonable and the images are very good. The marriage record will give you the names of both parties parents to help you get back another generation.
You will have an easier time as you get further back. There is a 100-year cutoff for Scottish records, so the earliest available census is the 1911.