Where are you located? I'm not sure that it's discontinued, click on this map
and see if there's a shop near you that carries it. You can find it online at Jimmy Bean's
, Little Knits
, and various other places.
It's a worsted or aran weight, doesn't have to be a merino. Knit Picks has a couple that could work (their Merino style is listed as dk, but it's as heavy as a worsted). There is only one merino, the wool that comes from merino sheep. There are superwash merinos, but that just means the item will be machine washable and possibly can be dried in a dryer.