I'm not sure how to get the dipstick tube out without damaging it, but that is definitely an item I want to save along with all the brackets on the front of the engine, it came from a non a/c car.
Wedge a bolt of the proper size into the top end of the dip stick tube. Then take a vice grip and clamp on tight to that bolted tube. Then rig up a chain around the vice grip and the other end of the chain on a slide hammer and yank that dipstick tube out of the block. It is only pressed fit in.