One used to paint trading vessel, a dizzying experience (6-7)

I believe the answer is:

roller-coaster

'a dizzying experience' is the definition.
(riding a roller-coaster might make you dizzy)

'one used to paint trading vessel' is the wordplay.
'one used to paint' becomes 'roller' (a paint roller).
'trading vessel' becomes 'coaster' (type of ship).
'roller'+'coaster'='ROLLER-COASTER'

(Another definition for roller-coaster that I've seen is " Fairground ride".)

I've seen this clue in The Times.

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