The next larger bolt is not going to work because it won't fit through the speedplay pedal body.
Also the width of the metal looks to be about 2mm, so not a lot of room to drill out and rethread.
The screw size apparently is 4-15. Do they make helicoil kits in that size?
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.