If so, who offers such a tag?
To answer your question, I reached out to Patrick King, the founder of Technologies ROI (TROI) and an expert on tags that can withstand high temperatures and harsh environments. Pat says: "TROI offers two tags tested for extended periods at 300 [degrees] C and even able to be read at 180 [degrees] C, which is remarkable (most tags go to sleep around 80 [degrees] C). Higher exposure is possible, but depends on time of exposure and mounting conditions."
Pat also forwarded links to several YouTube videos showing TROI RFID tags being exposed to temperatures of more than 1,200 degrees Celsius for short durations (about 30 seconds):
• Video 1
• Video 2
• Video 3
—Mark Roberti, Founder and Editor, RFID Journal