I used to get this when I ran Viva's as a teenager. It was no great issue. Just go down the scrappy and find the best of the selection in the yard and fit it. Now I have the same issue again and have a spare to go in (Thanks Fred ).
Question - How have you got around this particular problem? Indeed have you ever had it?
This is the one that came out. As you can see this particular box has been heavily strengthened. Still bent the arm though!!