I would be stunned and amazed if there were Barras there.
Post the same question on UKSWFF forum...some of the guys might be able to help you out.
http://www.ukswff.co.uk/They will most certainly be able to suggest flies for the Bass and Mullet
Surf Candies and the like should take the bass, dressed with green, chatreause or blue backs. The Orvis shop in Banchory has saltwater flies..they are in boxes under the trout fly display...sandeels, surf candies, crab and shrimp patterns etc.
Mullet will take flies that look like maggots (Sawyers Killer Bug) or a hook wrapped in white marabou and left to sink very very slowly. A 6 weight is a good rod for this.
I would also take some Clousers, Crazy Charlies (great shrimp pattern) and poppers.
Hope that helps a little.