Where can I buy a really good quality santa costume?

Where can I buy a really hood quality santa costume?

Obviously not for this year, but some friends have asked me to be santa for their kids. Is there somewhere in the UK, or even a trustworthy website you would recommend? I don't mind spending triple figures if it means I have the outfit for life.

I adore all the kids my friends have, and I'd love to make Christmas next year special for them.