Hey man! I have found the perfect mask and costume for SCP-049! Its only like $34. Here are the links
Mask: Amazon.com: Disguise Costumes Silver Venetian Mask, Adult: Clothing
Robe2: Amazon.com: H&ZY Unisex Tunic Halloween Robe Hooded Cloak Costume: Clothing
Here is the one I use. The proper name of these long-beaked masks is a zanni mask from Commedia dell'arte, making it a little more difficult to find than the shorter plague doctor masks.
Note that the mask is traditionally only a half mask. For my cosplay version, I took a wide isosceles triangle of black cotton and stapled it around the lower edge to hide the rest of my face, though glue might work as well. Another wide strip of the same material pasted around the top edge should cover your forehead too if you need it.
