Who knows the exact box sizes for the inside of this box?

i wanted to make a inlay that fits nicely into the box, but for that i need the box sizes.

up until now i only got a pproximate size and not a exact size.

Maybe this will help you.

According to boardgamegeek.com outside box sizes are :

11.70 x 11.70 x 2.80 inches (29,7 x 29,7 x 7,1 cm)

Perhaps you might extrapolate inside sizes from these measures?