Window crank handle replacement

I'm looking for window crank handle replacements.  To right side and two left side. The product has an etching on it from Nordic, apparently the manufacturer.  The home was built around 1980, and this is the original window hardware.  From the point about which the crank pivots to the tip of the crank measures 11 and 3/8 in, and the bronze looking piece that actually sits on the window casing measures 4 in by 2 and 3/4.  Looking forward to your guidance on getting these replaced. Thank you.