Well Gman it depends on which model it is.If you check my thread below.
It's really an identification thread but you will be able to see the 3 different versions.
VC-125 Hopefully you will be able to see which model you have
I mean in generally they are getting hard to find,but the Mark II are harder to find and the Mark III are extremely hard to find.After a 6 year search I was able to finnaly get a Mark III and within that time I was only able to find 3.Two of which I have got.
See if you can throw some pictures up (preferably on the VC-125 thread) and I'll do my best to identify which you have have.