If you have a picture right click to select copy image location, click on the "add image" link in the answer box and paste in the image location on the first line in the pop up box and hit insert. Once I have an idea of what the blade looks like I can give you some ideas on how to sharpen it or find a video of someone doing it. All the good old tools were meant to be sharpened. Usually a diamond file to the cutting blade following the original angles is the best.
I take it that bung holes are tapered?
