Broccoli Cultivars suitable for hilly area

I am keen to grow Broccoli in Himachal in summer months. Being new to this , i am keen to know what are the best varieties (names) and the companies producing those seeds. Quite obviously, what i am looking for is bigger size of the flower, dark green colour and longer shelf life.

I would be very thankful for any fallow farmers to share his/her experiences with me on this.