CHAMPION 600: USA Made or MIM??

Hi All,
I have looked at all the photos I could find to see if the Champion 600 is US Made or MIM. I only see "Corona, Ca." on the back of the amp, does anyone know for certain where it is made. I'm going to say by the price that it is MIM.

Thanks so much.

China.

China.

thanks again.

I've got one by the way. With minor tweaks it's a great little amp.