The Anal Retentive Costume Site has posted amazing photos of the actual dinner corset they procured at the 25th anniversary convention in Vegas (hey, I was there!). For the longest time it was generally assumed the corset was black. Turns out it's a dark purple paisley print - but the velvet doesn't reflect much light. If you are going to use a paisley print, the darker the better. Otherwise, black will still look nice on stage, and is much easier to find!
The corset looks to be 8 panels; 2 center front pieces, 2 side front, 2 side back and 2 center back. The boning across the front is incorporated into the seams and supplemented in a fan-pattern across the four front panels. The top has subtle curving with a slight dip in middle and a more pronounced dip across the bottom.
The back part of the corset has 4 panels with boning in the seams, and an extra bone on the side back pieces at an angle. 8 sets of eyelets, flanked by more boning on each side of the eyelet channels. The lacing looks pretty much like black shoelaces knotted at the bottom and tied at the top.
The blouse is chiffon with a wide, rounded neckline. It has black shoulder pads and rips in the armpits and the left elbow. You could probably modify a store-bought top for this purpose.
The back part of the chiffon blouse has, by my count, 11 small 2-hole clear buttons. The button plackets are treated with the same embroidered mesh as the floral overlay. The button loops are black soutache, but elastic cording will also work (and fray less). At the end of the scene it looks like the chiffon has ripped away from the button placket.
The overlay is a series of large flowers embroidered with silver metallic thread. The overlay begins over the right shoulder, crosses down the chest and ends under his left breast.
Scattered around the entire top (mostly the chiffon blouse) are rhinestones, 9-patch rhinestone beads, some black "leaf shaped" sequins (hard to see, look on his right breast), and some 6-pointed star rhinestones (I have yet to ever find these).