Hi Matthew,
We have one tipcar (1001). 1002 & 1003 are just chassis - no dump apparatus remains.
The 1001 tipcar (as mentioned above) isn't really useful for ballasting operations - the ballast ends up too far away from the track. In fact, in the many years I have been involved with the WW&F, I have never seen the tip car used. It is usually kept on panel track that is disconnected from the main line.
I *think* I saw a picture of a dump car that the Silver Lake Railroad (Madison, NH on the Conway branch) uses. Something like that would be useful. I'll see if I can find the photo...