Calsap is one of my favorites in the garden (I happen to live but 30 minutes from Rare Find Nursery).

It's stunning when in flower, from anywhere in the garden. Mine has seen a bit of 'open' foliar growth, yet has budded up and has been a consistent 'good' flowerer in deep shade.

As for your plight, I feel for you as I know of no good rhodie nurseries in NE that could possibly assist you in your search. There are far worse things done or time spent in this life than making a point to take a ride down I-95 for these things. :^ )

The home of Rhododendron PJM is in MA. It is Weston Nursery of Hopkinton, MA. However, unfortunately they apparently don't carry Calsap. You might call them to make sure and if they don't, see if they can recommend an alternate source.

Rarefind ships if you need to order from them.

It is a great plant, a little open and has slightly yellowish leaves but is very hardy. It grows best in full sun.

Here is a link that might be useful: Weston Nurseries

Greer Gardens in Eugene, Oregon offers Calsap.

I bought R. Calsap this year at Carol's Collectibles in Ashford, Connecticut - not too far over the Mass. border in Eastern CT. Here is the website:
http://www.carolscollectibles.com/products.htm?cat=x91unj1i
My calsap was about 3' tall when I bought it and it bloomed beautifully. The phone number for the nursery is: 860-429-9589. Carol is a rhododendron specialist. Good luck, it is a very special rhody.

Kindly,
Jane

Here is a link that might be useful: Carolscollectibles