Player Piano Question

[John Ross]

I am trying to find a replacement for the things that are in the pedal  
linkage that look like bolts with no thread, and are held in place  
with a collar with a set screw.
I thought it would be easy, just get a bolt and cut the head off.
It measures about .25".
A 1/4" bolt is too small, and the next size up is too big.
I found one that I had got from PPC years ago, but it is too small,  
and uses fiber tubes to build out the size.
Any ideas would be appreciated.
The other thing is the holes they go into are elongated. It is a soft  
metal. Would JB Weld be the thing to use to fill it, and re-drill to  
size?
John Ross
Windsor, Nova Scotia, Canada