Purity: Insufficient Camphor for Camphorating
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 580:
If camphor cannot be procured, or if the quantity that can be procured is sufficient only for ghusl, then camphorating is not necessary. In the event that after ghusl an amount of camphor is left over but it is not sufficient for it to be applied to all seven parts of the body, then based on recommended precaution, it must first be applied to the forehead and then to the other parts if any is left over.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)