To get the weather and stock widgets in the lock screen, you would need to jailbreak. Then use LockInfo ($3.99 + 2 week trial) from the Cydia store. The app has other functions, but this is the main one. It's not perfect, as it currently shows a moon on the lock screen and a sun in the Weather.app
As a jailbroken iPhone 5 user, I'd say the added features available from Cydia are great but the battery life and stability of the phone take a noticeable hit. It's sort of a wash.