Sikas can be hunted at:
Assateague Island - state and federal lands, need to sign in and buy permit to drive on beach.
Blackwater National Wildlife Refuge - need permit
Fishing Bay WMA - free to hunt by land or boat
Taylor's Island WMA - no permit needed but need boat to get to better hunting (walk-in is blocked off by private club)
Chesapeake Forest Lands - no permit needed
If you want to hunt with an outfitter, I would suggest Muddy Marsh Outfitters. They are a couple of good guys who do nothing but bowhunting. The cost is about $330 for two days.