Experts are fucking HARD TO FIND. Been looking for one, for a long time.
I'd say just get a WA 1911 IED, get hogues, and modify them accordingly... There's not much you can do in terms of slide customization...

However, you can paint the mag catch, slide stop, safety, and whatever else is accented

to look slightly more "dante-tastic" .
I'm really interested as to how this goes!
Goodluck!