tranny- what part is this?

[SimpleSexy180]

Yeah well, my car started acting up when the clutch fork started squeeling and making this loud rattling noise inside the bellhousing. It would go away when i would press the clutch and i could feel the vibration to the clutch pedal. I took out the tranny and to my suprise the fork is ok and so is the T/O, BUT this metal tube/sleeve thing that goes in the middle the T/O is broken off from the back end of the housing that goes towards the gearbox. my question is wth is this part called so i can buy it and get it replaced and also it seemed to be attached to this peice that i took off with 6 bolts. If anybody can help plz respond

also its a 89 sohc..if that matters..