'Concretus' - You can salvage your original hand-guard, with the missing wood.

Make a 'Dam' with sticky tape, like Masking Tape:

1. Make a wall, underneath, with tape on the inside of the hand-guard.

2. Make a wall at the rear edge, with tape.

3. Mix Acraglass and darken it with the powdered stain that comes in the kit.

4. With the hand-guard sitting level on a 'safe' surface, (not a family heirloom table), pour Acraglass mixture into the form, you have made.

5. It may take a couple of pours, allowing the Acraglass to setup in-between, to get adequate depth of Filler.

6. File and sand Acraglass to a pleasant contour.

This will not be an invisible repair, but, it will be strong and functional.

Someone with good woodworking skills could do a nicer wood patch.

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