Option 1 states that the Gandhara art of the Peshawar Valley is known for some of the finest sculptures made in dark grey schist. This statement is correct. The Gandhara art, which flourished from the 1st to 7th centuries CE in northern Pakistan and eastern Afghanistan, is renowned for its exceptional sculptures made from dark grey schist. These sculptures depict a blend of Indian and Hellenistic artistic traditions and represent figures from Buddhist and Hindu mythology.

Option 2 states that the Kushanas were the first Indian kings to have portraits of themselves made in their shrines. This statement is also correct. The Kushanas, who ruled from the 1st to 3rd centuries CE in the northern parts of the Indian subcontinent, were known for their patronage of art. They were the first Indian rulers to commission and display their own portraits in their shrines. These portraits, usually found on the back walls of the shrines, depict the Kushana kings in a realistic manner and showcase their royal status.

Therefore, both statements 1 and 2 are correct.