Thanks for all the input on this. With the aid of a butt removal tool from DS Solutions and an unwelded carry handle retaining screw, my friend has succeeded in swapping the furniture over. He's intending to take a 'one will turn up eventually' approach to sourcing a wooden carrying handle assembly.

Apparently the trouble and expense involved is my fault as I told him when he got it that a 1963 Enfield would have started it's career in wooden furniture.
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