F58AM repair parts

I have a F58AM flash that took a tumble while attached to the camera the other day (!@#%$ cats!)...

The little retractable latch part that keeps the flash from sliding out of the shoe is the only thing that broke (thankfully).  So, as long as I am careful, I can still use it, but it would be nice to replace that little part.  I took a gander at the part out of my F56AM but it doesn't quite fit.  They are so close in shape and size, but not close enough.  So- does anyone have any idea how/where I can find that part?

Thanks,

BM