My T/C Omega is the Blue with Synthetic Stock.
I also felt that it was a bit barrel heavy.
I added 8-ounces to the stock and it really balanced the gun out nice.
Take two zip-lock sandwich bags, add 625 copper plated BB's on one bag. Roll the bag up and zip it, then place it in another bag and roll that up and zip it. Then a bit of duck tape to ensure that it stays closed. Then I took the foam that was in the stock and repacked everything in the stock.
Really balances out the gun nicely and does not make any noize. The nice thing about this approach is you can easily adjust how much weight you wish to add. I started with a pound (1250 BB's) and ended up with 8 ounces.

Plus, if you wish to return the gun to original just take out the bag of BB's.

Best,

Tahquamenon