And what was the Nazi budget for producing giant gold eagles? And I'm being serious, because they had a few of them about.

That wasn't a mere speech, it was Hitler's declaration of war against the United States before the members of the Reichstag (German Parliament). The declaration was given in the Kroll Opera House.

The Opera House was destroyed by allied bombing in 1943 and stormed by the soviets when they invaded Berlin. I couldn't find any specific evidence about that eagle, I doubt any such records exist and it was most likely scrapped for the Nazi war effort. In general denazification was thorough at destroying remnants of the Third Reich and across Germany similar eagles were melted down/destroyed or, in the rare case, just had the swastika removed.