BB spindles are interchangeable (sans Campy).
You will have to match the spindle cone distance to your old one or it wont fit your frame properly.
I have replaced more spindles than I care to think about.
It is an easy job if you have the right size replacement.
The local bike co-op has drawers full of decent spindles for interchanging.
For beater bikes I prefer the serviceability and adjustability of cup-cone BBs.
Or you can just buy a sealed bb and install if you have the tools.
Enjoy