Hi Cyndee, these are often on eBay and because they are fairly common, tend not to cost too much. The tube shape is less common than the regular round bulb shape, though.
One suggestion for removing the broken bulb is to break off everything that sticks up out of the base, leaving a rim of glass around the base above the threads. Then push the narrow end of a raw potato down on the base and glass rim, and twist it counter-clockwise.
I have a use for the broken base if you don't want to keep it (I might be able to use it to repair a broken bulb I have).
Chris