The floor above our garage dropped about 1/2 and inch, which made one heck of a noise and scared the heck out of my wife and I. I found that the I-Beam Support pole had completely rusted out at the base and dropped down on itself. It is still supporting the I-Beam, just not in a structurally sound way. I had fixed a leak into the garage that was caused by a broken gutter drain and a lack of cement between the blocks in the garage wall next to it. (This is how excessive water got to the pole to rust it out).

This leads to a number of questions:
1. Where would I find a new support pole, and do they have a specific name?
2. Should I cut out the garage floor where the old pole is and re-pour for the new pole or should I just re-use the same hole?
3. Is this something I can claim on home owners insurance as we have only owned the house for 2 years?
4. While I understand how to properly jack up the beam and replace the pole, is there any reason I should not try to do this job myself?