The lamp looked like a marriage to me, Frank, until I checked the bottom of the dome. Now I'm not sure. They look the same color. The color of the dome may be different because it looks better when lit. I don't know if the attribution is correct. I don't trust Antique Helper completely unless I see a label or know the glass. They do provide a good direction to look, however.
I agree with a silk or similar cloth shade. I doubt that the base will ever find a partner exactly like it. The harp on the lamp looks like it was made to support a simple dome.