Well, it's cracked. How bad is it?

The tube is "pressed", or a friction fit, in the block. All the methods chosen would've expanded it more, and increasing the difficulty. Acquire some drill rod just a smidgeon smaller than the tube's OD. From the top side, drive the remnant piece out. Flush the bore out with brake cleaner. Install the new one with some industrial epoxy at the bottom. Make sure there's release agent on the new tube so it is not glued in and can be removed if needed. The epoxy will give you a new "hole" and help hold things together.
Sounds reasonable. The tube looks pretty smooth on the inside so I'm not sure how much of it is still in there. I can see the beveled edge of the tube on the top so I know at least the top part is. So you are saying fix the crack with epoxy and install a new tube. What type of release agent do you recommend?