I have this radio in my collection. The label on the back clearly states model 528, it is a small tabletop in a wooden cabinet & is 10 5/8 inches wide by 7 3/4 inches high by 6 1/8 inches tall. There is also a ballast tube in the set & it's P/N is M-55-F. In addition, it does weigh in at slightly over 5 pounds.
My set has a permanent maganet speaker & it does look like it is original !!
I did enter your data (and a bit more) to the model. I hope it reflects what you wrote.
It is very well done to post this via model to the forum so it sticks to the model. You are invited to use the other link on the model "Suggest change". With this you entry your data directly to the model. Two model admins will then check before it is coming up.
But if you prefere ths way that is all right.