IIRC the Army had at least one on the islands. We were keeping an eye on their helicopter assets in case the opposition mounted a heliborne counter attack. We had had a tip off from TFHQ following a radio intercept which indicated that they were planning such an operation. A chinook would have allowed them to lift a substantial number of troops to a short distance to hit 5 Bde HQ. Unfortunately (for them, but good for us) their intended target was outside the range of their supporting fire so the operation never materialised, being cancelled at the last minute. Nobody told us though and we were stood to for a couple of hours...
Accodring to Wiki they had two Chinooks at Stanley, one was destroyed on the ground (pics can be found online) and the other was captured following the surrender.
The RAF LO at 5 Bde HQ nicked one of the servicable Hueys and it was used as a Bde HW runaround until the Crab grown ups cottoned on and told him to put it back.