Below is actually the most relevant section in that link but only applies to Debit cards... . You'd need to check with your credit card company to find out what their fee and minimum charge is for overseas spending. Loading fees are not charged separately they are calculated as part of the exchange rate.
Spending fees
These apply to debit cards and are flat-rate charges that some banks put on foreign transactions.
Lloyds TSB currently charges ÂĢ1 per transaction, except on its Platinum and Premier debit cards, Royal Bank of Scotland and Natwest charge ÂĢ1.25, and Halifax charges ÂĢ1.50 a pop.
You can avoid these charges by using a Nationwide debit card, which only has a 1% charge for non-sterling transactions outside Europe, while the Santander Zero current account has no fees.
Try this link for more overseas buying via debit/credit cards info