Lifeboats: the simple, cheap solution...
Very few ships bother to carry a single lifeboat large enough for everyone on board. Instead they have multiple small, cheap, modular lifeboats.
These already exist for the ISS. They are called Soyuz, and one is there already, allowing a crew of 3
If you dock 2, you can have a crew of 6
If you dock 3, you can have a crew of 9
Can anyone help with the rest of the maths?
The financial cost is low, the political cost is high. Imagine asking the RUSSIANS to pull the asses of Americans out of the fire! What loss of face.
Pity, because it is a cheap, workable, and immediately available solution (ISS already has a multi-access dock).