Washing Transmission Going Bad In Stacked Washer/Dryer Unit?

I just had a repair man come out to my house and he said that my washing machine "transmission" is going out. He said not to do anything yet as it is an "expensive" item. The problem is this is a "stack" unit and I was just wondering in order to prepare for the worst, should I consider replacing the transmission and keeping the unit (It is 8 years old) or should I look into getting a new set all together?

I guess I could also consider buying a used washer and setting it next to the "stack unit until the dryer goes out! But that would sure take up a lot of room. Hmmm, then I could use the "old" washer tub to hold dirty clothes... Anyway I would appreciate your collective help!

TIA

Cookiepom from Wwensboro, KY