It's my understanding that blended scotches run from 5% to 95% malted scotches. My guess is Johnnie Walker Blue would be your best example of a 95%. There's also a Scotch - Lombard Gold that is supposed to have a lot of malted scotch in it as does Buchanans. You will not find many Scotch companies that want to give you that info. Dewars is supposed to be "51%" malted scotch.
Here are a few pure malted scotches, which are a 100% blend of single malts.
All the Compass Point Scotches
Cutty Sark Malted Scotch