Well I'm not sure of any wonderkid keeper as in my Career at United I have De Gea so havent had to look.
But you could look at the teenage keeper at United V.Savic. I'm only at the end of my second season so I dont know how well he develops but his attributes look pretty decent. So much so that now with Lindergaards contract expiring I will promote him to primary back-up for my 3rd Season.
So you could scout him and have a look.
Sam Johnstone from Man United is always a good GK.
Not sure how Scuffet hasn't been mentioned but he becomes arguably the best keeper in the world.