Paying large sum of money to NI business, anyway to lessen exchange rate damage?

Hi,

Not sure if this is the right place but I need to pay £5888 to a NI business. Obviously with the exchange rate being so poor, the amount in Euro is going up and up.
I knows theres nothing major that can be done and its just how these things go sometimes, but is there any way I could lower it slightly?

Would I get a better rate if I changed the money into cash sterling here and then put it in my UK bank account? Is that even legal?!

Edit to add the balance isn't due till July but it doesn't seem like the rate is going to get any better.