It's still on their website. Under "Photography > Traditional B&W Paper > Ultrafine Silver Eagle. I'm about out myself, so will be ordering more very soon. I don't use 16x20, though, so you can have all that.
Yes, it's there! I have a pack of it in 5x7 and it is a good paper. Not my favorite, but if it were the last paper standing I could get by just fine with it. John W