graemeh:
You are not an unsecured creditor if you pay *after* the business is placed in receivership. I do agree though, get on to the bank about a chargeback.
It may however be difficult/time consuming to prove when exactly it went into receivership, and exactly when the order was placed. If they haven't received the goods they paid for, then it is simple, they should issue a chargeback, but give the company warning that if they aren't refunded within a few days a chargeback will be requested. Don't the company have to pay extra when their customer makes a chargeback?