I'd have thought 150g would be plenty. I made a scarf using 3 balls of whisper wool and it made a scarf long enough to fold in the middle and tuck the ends through the fold - do you know what I mean?
Or you could wrap it round your neck fully once or two times.
Hope this helps
Eyelet Cardigan using Rowan All Seasons Cotton from my stash (if I can get gauge)
Monkey socks from Knitty
Some socks with my beautiful yarns from Angelia
Sahara in Tilli Thomas Pure and Simple and Rock Star in colour Hope
My variation on the Anthropologie Capelet
A cabled hand bag for my friend (Still awaiting some bamboo handles!)