G'day,
Assams can be quite brutal, for caffeine, and are usually quite
common (in lower grades) in supermarkets. If you're in the UK, most
large Sainsbury/Tesco branches have a sizeable range. So-called
"breakfast teas" are usually quite eye-opening, but they're not going
to set your tastebuds alight with pleasure.
Toodlepip,
Hobbes