According to this journal article, in 2016 the Russian 152mm GPS/GLONASS-enabled artillery shell cost $1,000.
The U.S./ NATO 155mm M982 Excalibur artillery shell cost about $80,000 to manufacture. In 2022 the cost of Excalibur has been significantly reduced though.
Charles K. Bartles, “Innovation, Cost, and Compromise Regarding the ‘God of War,’” OE Watch Online, June 2016