Salmon yummy! Can you get oysters on the NHS?

Wikipedia says:

"Dietary sources
In some countries, staple foods are artificially fortified with vitamin D.[108] Dietary sources of vitamin D include:[1]
Fatty fish species, such as:
Catfish, 85 g (3 oz) provides 425 IU (5 IU/g)
Salmon, cooked, 100 g (3.5 oz) provides 360 IU (3.6 IU/g)
Mackerel, cooked, 100 g (3.5 oz), 345 IU (3.45 IU/g)
Sardines, canned in oil, drained, 50 g (1.75 oz), 250 IU (5 IU/g)
Tuna, canned in oil, 100 g (3.5 oz), 235 IU (2.35 IU/g)
Eel, cooked, 100 g (3.5 oz), 200 IU (2.00 IU/g)
A whole egg provides 20 IU if egg weighs 60 g (3 IU/g)
Beef liver, cooked, 100 g (3.5 oz), provides 15 IU (0.15 IU/g)
Fish liver oils, such as cod liver oil, 1 Tbs. (15 ml) provides 1360 IU (90.6 IU/ml)
UV-irradiated mushrooms and yeast are the only known vegan significant sources of vitamin D from food sources.[109][110] Exposure of portabella mushrooms to UV provides an increase of vitamin D content in an 100-g portion (grilled) from about 14 IU (0.14 IU/g non-exposed) to about 500 IU (5 IU/g exposed to UV light).[111]"