As used by loads of military people, try:
Buffalo - Fleece Jacket
https://www.cotswoldoutdoor.com/webp...on=brand_intro
and/or
a Softie.
http://www.snugpakclothing.com/produ...sp?JBProdID=44
I have both and wear them on their own or even together (with no other layers) when fishing in winter. Been quite happy sat still for our in freezing conditions.