Are there any sources for native New York azaleas? I'd prefer to buy from a New York source, if at all possible.
Your parents' fragrant, native azalea was very possibly Rhododendron periclymenmoides (synonym R. nudiflorum), or pinxterbloom azalea. It is a deciduous native to New York, happy to grow in shaded woodland, fragrant and has abundant flowers, either pink or white, from April to May. Here is a photo of a pink one blooming:
There are numerous nurseries that specialize in native plants, though some stock other plants as well. Some native plant nurseries serving central New York include The Plantsmen Nursery in Groton, NY (75% native plants) and Edge of the Woods Native Plants Nursery in Orefield, PA (100% native). It is too early for many nursery growers in these northern zones to be open for business and many do not even have their plant lists available for 2017 yet.
If you would like to further search for azalea species that are native to New York, you should look at the Lady Bird Johnson Wildflower Center website and search under Rhododendron and then narrow your search to the state of New York. If you can determine what azalea you'd like to purchase, you can then search for it online and select a NY nursery, if possible. There is such a proliferation of azalea cultivars available that it can be difficult to locate the specific plant you are looking for but we commend your interest in keeping your search native and the plant's suitability for your garden should reward the search.
Good luck with your garden and let us know if we can be of further help.
Courtesy of NYBG Plant Information Service