The nurseries and garden centers should have or will soon have pansies.

In zone 7 you are not all that limited - dwarf conifers, dwarf Japanese maples, many smaller shrubs and pretty much any perennial you like. A variety of perennials are evergreen or very nearly so - hardy euphorbias, hellebores, heucheras, bergenia. All of these look good in winter/early spring and you can fill in with color spots of pansies or primroses and swap out with other annuals later in the season.