3 days to dispatch is perfectly resonable. Once dispatched it is in the hands of the postal services and sometimes they are fast, sometimes they are slow.
The T&Cs of the company wesbite (which you have to read and agree to BEFORE making your order) clearly state................
"Orders are usually dispatched within 48 hours of receiving payment. In some cases orders are dispatched the same day as the order. Orders made at a weekend will be dispatched the following Monday at the earliest. However, we cannot guarantee the above and there may be times when orders take longer due to unforeseen circumstances, e.g. a large order, which will take time to process, has been received prior to your order. If your order is urgent or you require special shipping methods then contact us BEFORE you make your order to arrange this. If you do not do this, the item will be sent via standard First Class mail and will therefore have no guaranteed shipping or delivery date. "
So if you needed it urgently you should have made arrangements before clicking the ACCEPT button.