There are moorings in -

Blue Lagoon, St Vincent
Admiralty Bay, Bequia
Britannia Bay, Mustique
Charlestown Bay, Canouan
Salt Whistle Bay, Mayreau
The Tobago Cays
Clifton Harbour / Chatham Bay, Union Island

If picking up a mooring anywhere south of mainland St Vincent, you should snorkel over the mooring to ensure it's properly laid and that the fittings and lines are OK. There have been many instances of moorings, with attached yachts, heading out towards Guatemala in the middle of the night or of lines parting.

Let your good lady know that she should sleep soundly if the vessel is correctly anchored but that she should have one eye open if on a mooring! The anchoring in these parts is straightforward, generally in an all-sand bottom, in anything from from 6 to 20 feet, and with excellent holding.