If the scrolling doesn't contain any tight curves and you can get into
the curves to clamp it, veneer would work. I'd probably avoid the
self-adhesive stuff and the iron-on stuff won't work well.

Another alternative that you might use is make an applique of solid
wood to put along the top. This could be a piece of 3/4" stock with a
rabbet in the back for the plywood. At most the plywood gets a curve
across the top. The solid wood gets the scroll work and fancy stuff.

G'luck.

Dave