Corrupt Audio fix, possible?

I've got an ancient first copy audiobook of Steven Kings Gunslinger from the dark tower series. My sister wishes to read the book but I cannot find my paperback copy, and win I opened this audiobook again it will play for a while, then lurches from just before the Tull church scene to where Roland meets the boy. Once the book is over it starts the part it skipped. Can I cut that out somehow and paste it back into the correct spot?