Antoninus Pius and Marcus Aurelius, as Caesar. AE Sestertius. 
140-144 AD. 

ANTONINVS AVG PI-VS P P TR P COS III, laureate and draped 
bust of Antoninus Pius right.
AVRELIVS CAESAR AVG PII F COS, S C in exergue, bare head of 
Marcus Aurelius right, slight drapery on left shoulder.

RIC III 1219. 

Courtesy of Stack's Bowers and Ponterio 
Sale 173 January 2013, lot 6168, sold for $375