As you are asking for the AIIMS institute in Himachal Pradesh

At present it is not places at Himachal Pradesh

But it is suppose to establish at Himachal Pradesh

Here is list of the upcoming and planned AIIMS:

AIIMS Nagpur, Maharashtra
AIIMS Mangalagiri, Andhra Pradesh
AIIMS Rae Bareli, Uttar Pradesh
AIIMS Kalyani, West Bengal
AIIMS Gorakhpur, Uttar Pradesh
AIIMS Bathinda
AIIMS Madurai, Tamil Nadu
AIIMS Bilaspur, Himachal Pradesh
AIIMS Jammu, Jammu and Kashmir
AIIMS Srinagar, Jammu and Kashmir
AIIMS Assam
AIIMS Saharsa, Bihar

The AIIMS institutes are located in:

Name State/UT

AIIMS New Delhi Delhi
AIIMS Bhopal Madhya Pradesh
AIIMS Bhubaneswar Odisha
AIIMS Jodhpur Rajasthan
AIIMS Patna Bihar
AIIMS Raipur Chhattisgarh
AIIMS Rishikesh Uttarakhand