Thought I'd post the outcome in case anyone is interested. I have no access to welding gear and no experience, so I ended up finding a welder via my school's physical plant department. He brazed the pedal with something called Quicksilver, a phosphorous-copper alloy. In my opinion he did a very nice job. He not only filled the hole, but built the metal back up to its original profile. The filler is a different color, but this is a practice room piano so that's not an issue. The cost was about $150, more than a new set of pedals would cost, but it saved me the work of modifying the box. The best part is that I now know a good, affordable welder.
Thank you all again for your input.
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Benjamin Webster RPT
Albuquerque NM
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