Plating over firescale & Worn out Prip

 Can I silver plated over the firescale, or does the firescale
have to be removed first for the silver to properly adhere? (I
would use a commercial plating company) 

Yes, you can plate over the firescale. I recommend P.J. Gill at 9
Fowle Street, in Woburn, MA.

    2. During the soldering which caused the firescale in the
first place, could I have sprinkled powdered borax on the hot piece
when I noticed that the Prips was wearing out? 

yes, you could have. You also could have added more Prip’s
Flux–either by spraying or brushing it on.

Cynthia Eid