Reg playing with metal wire (8)

I believe the answer is:

'wire' is the definition.
(I know that wire can be written as telegram)

'reg playing with metal' is the wordplay.
'playing with' indicates anagramming the letters.
'reg' with its letters anagrammed with 'metal' makes 'TELEGRAM'.

(Other definitions for telegram that I've seen before include "Electric message" , "Now obsolete communication over a wire" , "Dispatch" , "cable" , "It may bring word" .)

I've seen this clue in The Sun.

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