I got this Nantucket Basket Michael Healy Door Knocker for our front door. It has a plastic insert that allows you to put live flowers inside – although when it is warm it is hard to keep anything in there alive. I don’t think anyone has used it for knocking, but it is super cute!
EasterKiwi 
That is really unique! I’m not sure if yourhomesupply.com has door knockers, but I do know that they have a great selection of door hardware that might go perfectly with that door knocker. I just thought I would suggest that site since I myself am working on giving my front door a face lift and ordered a handle-set from them. I hope it helps!