auto gear box leak

Hello can anyone help i have just bought a disco 2 4.o auto es model ,just thought i would check auto box level before going away to find where the cooler pipe screws into the bottom of the box some dick head has broken half the thread gear box side so when you screw in the cooler pipe only half of the thread is holding ,do anyone know of any way around this or am i in for a new gear box any help would be appreciated.

what age ? oil cooler pipes go into pump housing polate it isnt a hard job to change it once box is removed from vehicle ,

The discovery is 2003 plate ,also are these pipes under a lot of presure ? i was going to try and temp fix it untill i can get the box out with liquid metal or bridging filler many thanks for advice, Nick.