My home made vise I mentioned above is built on a bowling ball as well.
Cut off with a band saw, yes they are rough on the blade!.
Then the core chiseled out to make room for a mix of lead shot and epoxy for added weight and to anchor the
home-built vise that sits atop it.
The vise made from scrap dimensional steel bar and plate.
It all sits in a simple shallow 3 edged box for stability on a potters wheel type set up.
I engrave primarily while sitting. About the only thing I do standing is barrels. I just plant the entire vise in a separate upright post at the other end of a bench with a similar 'box' for it to sit in.
The box allows for the vise inspite of it's just under 50# weight, to be tilted quite easily when working.
No vibrations.
It's worked for me for all the time I was full time and I still use it.
A lot of gunsmithing work gets done on it too.
A couple messy bench pics (the normal look) You can see the vise , kind of, partially,, in the pics.
Not pretty, but it does the job!

