PUFA sources

ω-3 sources (EPA, DHA):

(cold water, especially seawater) fish, seafood, fish oil, krill oil – more info on fish here
some seaweed / micro-algae (original source of EPA, DHA also for marine animals) – commercial products chlorella, spirulina
PUFA can also be found in meat, animal fat and eggs – but in a very small proportion. Moreover, there is more ω-6 than ω-3 there (this is even more prominent in case of factory farming) – it is recommended to focus on grass-fed animals

ω-3 sources (ALA):

(fresh) ground / crushed flaxseed, flaxseed oil (4: 1), chia seeds (3: 1)
kiwifruit seed oil (5: 1), perilla (4: 1) camelina (4: 3), sea buckthorn (1: 1)
walnuts – ALA alongside predominant LA 1: 4 (OK since nuts eaten in whole contain antioxidants)
(high quality, non-hydrogenated, unrefined) vegetable oils (rapeseed 1: 2, hemp 1: 3, soybean 1: 7) – ALA alongside predominant LA (ie these oils are not always the ideal source if we explicitly aim to reduce ω-6 – depends on the ratio)
spinach (5: 1), purslane (1: 1) – (lower ALA content, approx. 0.2% spinach and 0.4% purslane)
other leafy vegetables (cabbage, kale, lettuce, arugula) as well as kohlrabi (1: 1-2: 1) – (ALA approx. 0.1%)

ω-6 sources in general:

In more detail – AA together with LA:

meat (especially liver) and animal fat, eggs (AA in very small quantities, LA, while majority is SFA)
especially freshwater algae, fish (AA in very small quantities, LA, alongside ω-3 PUFA and SFA)

ω-6 sources (LA only):

almonds, hazelnuts, peanuts, pistachios, peach seeds
(quality, non-hydrogenated, unrefined) vegetable oils (sunflower, maize, wheat germ, poppy, melon and grape seeds, or less traditional plants such as evening primrose, safflower, sesame, prickly pear, or cotton
walnuts, flaxseed oil, chia (alongside ALA)
oils where ALA is also found, especially rapeseed, hemp and soy, but also others (see ω-3 sources)
olive and palm oil (around 10%, the remainder being MUFA and also SFA in palm oil)