You may go to your local trophy/engraving shop and have a small brass medallion about that size engraved with an inscription of your choice ( limited only to your imagination ) and inlay in the knot. As for the experience on a very expensive front door ( the trim carpenter drilled a 1/2 inch hole that didn't belong there. on the interior), yet rather than replace the door, ( which I offered to do of course at no expense) the home owner challenged me with an alternative remedy. I went to the trophy shop and had a brass medallion made with the owner and his wife's name and year the house was built, thus, personalizing the house to them. He thought it was great and she loved it and it brought tears to her eyes. He told me years later that when visitors come to their home they all enjoy the medallion, but he hasn't the heart to tell them it hides a mistake. Now every house I build , at the finish I present the owners with a medallion. It only cost a few dollars and makes quite an impact.