I had a SW PC tuned 4506-1 at the time.
My guess is 95-96-97 or 98, my dad and I were walking the Houston Gun Show and I came across a CQB 4566 that I too did not know it existed. Back then, gun money was tight for me. My dad insisted that I get it and he would pay for it.
I decided not to put my dad through a hefty expense of IIRC of 8-900$.
when I got home..... sold a buddy my 4506-1 and found a 4563 CQB.
Sometime after that, I was talking to someone on the phone at a ammo company and told him I was looking for a 4566 CQB.... he had one.
Back then, we were not allowed 1911 on duty carry.... so DA first shot was the only option.
My main duty carry was the 4563 out of a SSIII holster.
the good ol days.