Fully equipped spring discovered (4-5)

I believe the answer is:

well-found

'fully equipped' is the definition.
(I've seen this before)

'spring discovered' is the subsidiary indication.
'spring' becomes 'well' (I've seen this before).
'discovered' becomes 'found' (finding is a kind of discovering).
'well'+'found'='wellfound'

(Another definition for well-found that I've seen is " Fully equipped".)

I've seen this clue in The Telegraph.

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