If you're looking for stuff this summer, might be a bit late... Some companies like Mott MacDonald are usually quite good but that has a load of options aside from business. Others like HSBC also have an application-based system but not sure if that's open at the moment. Best shot to get what you want is to directly reach out to senior staff at local businesses you want WXP in as early as you can. The earlier and the friendlier (but still professional) you are, the better. Best to send out a short 1 page CV or something with who you are and what you do on it too.
You could also ask your parents/guardians if they might be able to sort something with their office potentially, or one of their friends.
It's also worth reaching out to the non-medical arm of your local NHS trust, they're usually decent with accommodating people in areas such as finance, business, co-ordination, etc.
Good luck to get what you want!