博器 is a rare/literary term —
博 here is the classical
博 of
博弈 (bóyì, 'gambling/games of chance', also chess and Go).
博器 referred to the dice, counters, and boards used in ancient Chinese gambling games like
六博 (liùbó, an extinct two-player race game). Modern Chinese uses
赌具 (dǔjù) for gambling tools.
