Rascal occasionally purchases computer for stray friend? (1.1.1.1.1.)

I believe the answer is:

rspca

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'stray friend? 1 1 1 1 1' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'rascal occasionally purchases computer' is the wordplay.
'occasionally' means one should take alternating letters (letters taken at regular intervals or occasions).
'purchases' indicates putting letters inside.
'computer' becomes 'PC' (personal computer).
The alternate letters of 'rascal' are 'rsa'.
'rsa' enclosing 'pc' is 'RSPCA'.

'for' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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