If you decide to replace your mag plate, the same 72-790 plate was used on several different models.
With a little bit of determination, you should be able to get that mag looking and sparking like new again. The original capacitor (condenser) for these mags was rated at .27 – .33 microfarads but in the photo I’ve used two axial caps rated at .15 mfd hooked up in parallel to get the same .30 rating.
Mumbles
Mag plate looks good! Did you sand blast? What product did you use?