Don't know about finding it cheaper, but I LOVE Misti Alpaca. I have knit several projects using various weights.
One thing about the chunky is that it has a lot of loft, so it knits "down"--not like a real chunky yarn. When I made a scarf, I put a knit-along yarn (Online Punta) with it and made the fringe really long in the Punta. The scarf is one of my favorites!! Sooooo sooooofffffftttttttt.
What color did you buy?