I don't see a stat entry on the tables, and they are only listed in the sub text on the Bola entry. Would this be an armorer test to create, or are they sold like that, a bola that has been adapted to contain two throwing grenades? I see no availability stat for a boom bola.
So I'll assume that if you buy one, its simply pay the cost for a bola, the cost for two grenades, and for rules its standard Bola rules with a-2 Accuracy to the Physical limit.
And I guess to be a right out jerk you could make a monofilament boom bola if you have nuyen to burn.