[VAC] Broken trailer jack - help

[Amores911]

Hello Folks:

My 44 year old jack on the front of my trailer has apparently had enough!  
The other day, I tried to crank the trailer up to hitch it to my tow vehicle
when it collapsed, sank back down, and now when I turn the handle, nothing
happens.  Does anyone know how to repair or replace this most essential item?
 Thanks for any suggestions.

Jon Amores #5437
1957 Caravanner