+1 on the TiGoat Raven Bivy
With the added full bugnet hood and shipping, this bivy comes to your door at $138. And it's great. Mine weighs 7.7 oz. Paired with my MLD tarp, it's a fantastic combination, IMO, coming in at just about 1 pound.
It is plenty long and holds my 6'6" WM bag with room to spare at the top and bottom for all my other gear.
TiGoat offers a side zip option too which seems like another good option.