transmission compatability

I bought the car used a week ago so as far as I know I have an 89, 4 cyl, 2.0, 5 speed cable driven manual trans, Cavalier. They want to charge me $1600 to fix a bunch of parts in the transmisssion includeing the clutch because of some damage that occured from heat. No way can I afford that. The rest of the car isn't in great shape either. I hope to buy a used transmission online for them to install so I only have to pay labor but need to know if this one's compatable. Here's what the site says.

1989 GENERAL MOTORS CHEV. CAVALIER (Interchangable part is a 1989 CHEV. CAVALIER) M.T. 4-121 (2.0L) cable drive speedo TRANSMISSION / Same Year or Newer part only Actual year:1989 Miles:1,000 Comments:MT 4 Cyl OLD TAG 0000000048

Sounds like it'll fit but I know very little about cars. Don't know how many variations or the cavalier tehre were. I would appriciate any help.