Grips for Marui Detonics, but with heavy weights
 

I am looking for grips to upgrade my Detonics and i found a lot of fine ones but it is impossible to fit weights.
Much of the "almost real" weight of the Detonics is due to the weights under the grip and don't want a nice looking pistol with a bad weight due to new grips.
Anyone has found a solution to this issue or a pair of real wood grips with enough space inside to contain the weights?

Full metal upgrade kit?

The full Upgrade is alluminium and its weight is similar to stock frame and slide