John & Alex do indeed have a custom made EI dissy in the drag car that IIRC has an XE Falcon top mated to the Holden drive shaft. They would be able to give you the contacts to obtain one of these, and an idea of cost.
The other option is a
Crane Cams Fireball kit, which I've got in my red-powered FE. I'm aware of another member who has successfully fitted it to a grey, and is very happy with the performance. The only thing you need to do to make it fit the grey dissy is remove the internal post that locates the old points, as it fouls the optical disc. (The diameter of a grey dissy is a fair bit smaller than the red one.)
There's also a
high performance version. Basic version is about AU$160, hi-po $250.
Hope that helps,
RET