|I need to know if you have any varieties of azalea that, at maturity, only reach somewhere in the 18-24|
|Morning sun is a great spot for these shrubs. Also be sure the soil is somewhat acidic, humusy and organic, and evenly moist yet well drained -- meaning damp like a wrung out sponge but not sopping wet or saturated. They are not well suited to heavy clay soil, for instance. Winter wind protection is also helpful.
This is quite small for a mature azalea, as most of the so called smaller varieties have a ten year size of between 3 and 5 feet. Your zip code places you in zone 7A, the colder part of zone 7, so to be conservative you might want to look at azaleas considered hardy to zone 6.
There are many dwarf and low growing hybrids available. Your local nursery may offer some (selection is usually widest in the spring), or you may have to go the mail order route through a specialty nursery such as Greer Gardens. They include numerous lower growing types in their current catalog to help you get a feel for your choices.
There are so many to choose between it will really depend on your personal taste and overall garden plan which ones to use. Enjoy your azaleas!