To answer my own question above. Workwear London in 129 Whitechapel Road just sold me a pair of waterproof trousers for 5 quid.
These are the kind of flimsy things they started making in the 80s before GoreTex was invented, but that also means they wrap up to a really small bundle that I intend to keep in my bag for those 3 days a month or so when it starts really pouring down. (with normal rain I am fine with jeans) My mate says they'll develop small rips here and there after a bit, but still largely works after a year of occasional use.
To answer my own question above. Workwear London in 129 Whitechapel Road just sold me a pair of waterproof trousers for 5 quid.
These are the kind of flimsy things they started making in the 80s before GoreTex was invented, but that also means they wrap up to a really small bundle that I intend to keep in my bag for those 3 days a month or so when it starts really pouring down. (with normal rain I am fine with jeans) My mate says they'll develop small rips here and there after a bit, but still largely works after a year of occasional use.