What about ground flax seeds (which you can sprinkle on most foods), flax seed oil, seeds,
nuts (except cashews, hazelnuts, and macademia
nuts - which are all higher in saturated fats), chia seeds, and/or hemp seeds/milk? Also, avocados are an amazing source of monounsaturated fats - and delicious. Or, you could actually eat fatty fish, like salmon, trout, or albacore tuna or even anchovies/sardines. These foods are generally high in Omega-3s.