I say use what you have. You will kill more birds being out in the field then you will sitting behind the computer wondring what it takes.
You could use black trash bags, but once the sun is up they will have way to much reflection.
Also, until your new decoys arrive, you will probably not be able to finish birds, meaning they will not commit to landing. Just like with deer or turkey, if you can get them close enough, you should be alright.
Good luck and happy hunting!!!!!!!!!