Vintage, Oscar de la Renta, dress in size 4

Oscar de la Renta, vintage, dress in size 4. Looks like two pieces. Dress has a dropped waist with a leather belt. Also, partial zipper up back and bottom (skirt) is pleated and has two side pockets. Bottom is black and white boucle. Measurements are approximately 14.5” pit to pit and length is 43” from mid shoulder to hem. Please see last photo. One sleeve just needs small repair. Sleeve hem needs to be tacked. Dress is in very good used condition. Classic.