Looking for exercise bike crank arms

[Toeslider]

So, a teacher at my school has an exercise bike in her classroom that has two stripped out crank arms (at the pedals). Looking for a couple square-taper crank arms, size isn’t a huge deal, but the important thing is that neither arm has a chain ring attached to it. Needs to be a left and right, thought about using two lefts but the pedal will unthread.

Anybody got anything in their parts bin?

 

[RustyGold]

If 1/2"-20, you could probably drill them and tap them to 9/16"-20 (you can pick up pedal taps pretty cheap). Or, you can heli-coil them...but, that isn't particularly cheap.