That's the exact same pen that my Dad used for many years as well. The only pen I ever saw him use. It sits on my desk, but I can't bring myself to use it. Good memories though.
I have a Fisher in titanium finish that I like to use and rides in my pocket always. Very handy pen.
You should go ahead and use your dad's pen. Every time you sign a check or anything, you'll honor him a bit with a memory.