Any wooden window frame with a single glass is easy to turn into a double, having received a kind of glazing is not worse than common now brand.
This will require a brace or composite rod-the glass bead and a slightly larger format than is setup in the window so that you can lay on the frame and press with rail, bothering and seal with a rubber strip or putty.
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To score a long thin nail, and especially copper or brass (e.g., with mounting frames) is always a problem. Will help you in this case, the conventional pliers or a wooden clothespin.