Heat half the oil in a large frying pan; cook onion, pine nuts and garlic, stirring, until onion is softened and pine nuts are browned lightly. Add rice; cook, stirring, for 1 minute. Add herbs, sultanas, juice and remaining oil; remove from heat.

Rinse vine leaves under cold water; drain well and pat dry. Line base of a large heavy-based saucepan with about 10 of the damaged vine leaves. Place another leaf, vein-side-up, on a board. Cut off stem if it's attached. Place 1 level tablespoon of rice mixture in the centre of the leaf, above the point where the stem was. Fold in two sides; roll tightly to enclose filling. Repeat with remaining leaves and rice mixture.

Place rolls, in a single layer, on leaves in the pan; pack in tightly so they cannot unroll during cooking. Cover dolmades with lemon slices, then remaining vine leaves. Place a large heatproof plate on top of dolmades so they can't move during cooking. Add the water to the saucepan; bring to the boil. Reduce heat; simmer gently, covered, for about 1 hour or until the rice is cooked.

Serve dolmades at room temperature.