The solder sleeve or splice suggested by Lindsay might be plausible. One would have to check dimensions for options.
As for connectors, I don’t think you will find any that are capable of meeting your specifications. As the connectors get smaller, the current and voltage ratings tend to drop. Getting a connector small enough to meet your dimensional specs will make the 340Vrms voltage spec nearly, if not absolutely, impossible to meet.
The smallest connector I could find is the SUHR-02V-S.
It’s a tiny connector but still a bit larger than your max physical requirements. Even so, the largest wire it can take is 28AWG, the max current is only 1A, and the max voltage is 30Vac, which is nowhere near your 340Vac spec.