1989 suburban transmission

I was wondering what type of transmission would fit into a 1989 chevy suburban. I am interested in buying a suburban that has the transmission out of it. What could I take the transmission out of?
Any help is very appreciated.

In 89, the 350 engine came with a 700R4 (4L60). The 454 (I think) came with a Turbo 400 (3L80).

//2000CAYukon

The 1/2 tons came with the R700 and the 3/4 tons came with the T400 that year, regardless of engine size

Blazers, Suburbans and pickups commonly use similar running gear. You can check http://car-part.com/index.htm to search your area/region. You could also talk to your local wrecking yard operator, they will have access to an interchange book which will tell you what will work.