Trade Club website lists 98 batteries for the Omega. All you need to do is find a participating dealer  

 Your search for Omega 94- 03 returned 98 results.
Omega ('94-'03)
Batteries
Application    Description    Part No.    Retail    Trade    Trade Club    Wish List
2.0DTi - X20DTH    44 AMP    19001889    £49.00    £44.83    £38.75    
2.0DTi - X20DTH    55 AMP    19003129    £57.50    £52.62    £47.33    
2.0DTi - X20DTH    70 AMP    9201470    £98.00    £89.68    £69.49    
2.0DTi - X20DTH    50 AMP    93168488    £50.50    £45.45    £37.82    
2.0DTi - X20DTH    65 AMP    93189923    £76.00    £69.55    £53.91    
2.0DTi - X20DTH    85 AMP    93197903    £115.00    £103.50    £82.17    
2.0DTi - X20DTH    60 AMP    93197905    £57.50    £51.75    £44.90    
2.0i - 20SE    44 AMP    19001889    £49.00    £44.83    £38.75    
2.0i - 20SE    55 AMP    19003129    £57.50    £52.62    £47.33    
2.0i - 20SE    70 AMP    9201470    £98.00    £89.68    £69.49    
2.0i - 20SE    50 AMP    93168488    £50.50    £45.45    £37.82    
2.0i - 20SE    65 AMP    93189923    £76.00    £69.55    £53.91    
2.0i - 20SE    85 AMP    93197903    £115.00    £103.50    £82.17    
2.0i - 20SE    60 AMP    93197905    £57.50    £51.75    £44.90    
2.0i 16v Turbo - X20XEV    44 AMP    19001889    £49.00    £44.83    £38.75    
2.0i 16v Turbo - X20XEV    55 AMP    19003129    £57.50    £52.62    £47.33    
2.0i 16v Turbo - X20XEV    70 AMP    9201470    £98.00    £89.68    £69.49    
2.0i 16v Turbo - X20XEV    50 AMP    93168488    £50.50    £45.45    £37.82    
2.0i 16v Turbo - X20XEV    65 AMP    93189923    £76.00    £69.55    £53.91    
2.0i 16v Turbo - X20XEV    85 AMP    93197903    £115.00    £103.50    £82.17    
2.0i 16v Turbo - X20XEV    60 AMP    93197905    £57.50    £51.75    £44.90    
2.0i 8v - X20SE    44 AMP    19001889    £49.00    £44.83    £38.75    
2.0i 8v - X20SE    55 AMP    19003129    £57.50    £52.62    £47.33    
2.0i 8v - X20SE    70 AMP    9201470    £98.00    £89.68    £69.49    
2.0i 8v - X20SE    50 AMP    93168488    £50.50    £45.45    £37.82    
2.0i 8v - X20SE    65 AMP    93189923    £76.00    £69.55    £53.91    
2.0i 8v - X20SE    85 AMP    93197903    £115.00    £103.50    £82.17    
2.0i 8v - X20SE    60 AMP    93197905    £57.50    £51.75    £44.90    
2.2DTi 16v - Y22DTH    44 AMP    19001889    £49.00    £44.83    £38.75    
2.2DTi 16v - Y22DTH    55 AMP    19003129    £57.50    £52.62    £47.33    
2.2DTi 16v - Y22DTH    70 AMP    9201470    £98.00    £89.68    £69.49    
2.2DTi 16v - Y22DTH    50 AMP    93168488    £50.50    £45.45    £37.82    
2.2DTi 16v - Y22DTH    65 AMP    93189923    £76.00    £69.55    £53.91    
2.2DTi 16v - Y22DTH    85 AMP    93197903    £115.00    £103.50    £82.17    
2.2DTi 16v - Y22DTH    60 AMP    93197905    £57.50    £51.75    £44.90    
2.2i 16v - Y22XE    44 AMP    19001889    £49.00    £44.83    £38.75    
2.2i 16v - Y22XE    55 AMP    19003129    £57.50    £52.62    £47.33    
2.2i 16v - Y22XE    70 AMP    9201470    £98.00    £89.68    £69.49    
2.2i 16v - Y22XE    50 AMP    93168488    £50.50    £45.45    £37.82    
2.2i 16v - Y22XE    65 AMP    93189923    £76.00    £69.55    £53.91    
2.2i 16v - Y22XE    85 AMP    93197903    £115.00    £103.50    £82.17    
2.2i 16v - Y22XE    60 AMP    93197905    £57.50    £51.75    £44.90    
2.2i 16v - Z22XE    44 AMP    19001889    £49.00    £44.83    £38.75    
2.2i 16v - Z22XE    55 AMP    19003129    £57.50    £52.62    £47.33    
2.2i 16v - Z22XE    70 AMP    9201470    £98.00    £89.68    £69.49    
2.2i 16v - Z22XE    50 AMP    93168488    £50.50    £45.45    £37.82    
2.2i 16v - Z22XE    65 AMP    93189923    £76.00    £69.55    £53.91    
2.2i 16v - Z22XE    85 AMP    93197903    £115.00    £103.50    £82.17    
2.2i 16v - Z22XE    60 AMP    93197905    £57.50    £51.75    £44.90    
...continued....