These bonds are obviously not common, so the banks don't like them! You will need a keen bank manager to be bothered pushing it through. As for risk, you will need to provide the bank with a personal counter-guarantee at least.
I know of one situation where the bank insisted on having an amount placed on deposit with them to the same amount as the guarantee (ie no risk) and still charged for the bond! This is why the bank relationship is important.
The size of the bond will depend on the brewing capacity of the brewery (ie basically how much duty could C&E loose if you defaulted), but would probably be at least 10k for a small brewery.
