The finest, sweet-scented Lavender comes from selected cultivars of English Lavender (Lavandula angustifolia). Furthermore, the best oil is extracted from blooming flower heads only, not leaves. Consider growing a few lavender shrubs. You could likely produce enough to supply the needs of your household. There are many cultivars available, especially online, but I've found that L. angustifolia 'Hidcote' is a commonly available cultivar that gives a very fine scent. Of course, double-check this if possible, as cultivar names may be misapplied.
The name English Lavender is something of a misnomer as Lavandula angustifolia ssp. angustifolia is native only to southern France and a small part of Italy. There is another subspecies, L. angustifolia ssp. pyrenaica, native to the Pyrenees of France and Spain.