Stone for Steep hill landscaping.

Stone for Steep hill landscaping. Images

Stone for Steep hill landscaping.

Stone for Steep hill landscaping. Description

Hi,
I have a lanndscaping project on a steep hill, gradient between 35 to 40 degrees, and (http://maplered.com) this is in south-east Pennsylvannia. Can anyone please suggest the natural Stone (http://g603.net) s suitable for a slope of this gradient and (http://maplered.com) also the distributors nearby?
Any other suggestions for a slope are welcome.
thank you.
Aparna.