You can try these files, they are for the i9000 but they should flash without any problems..
Hybrid TW Clock v2.4 SGS3 themed - http://www.mediafire.com/download.php?epc0valgetc4x71
Hybrid TW Clock v2.4 SGS3 themed + Extras pack - http://www.mediafire.com/download.php?s442l1qemcg0cvj
if they don't work you could open the zip and take out the files and copy them across manually to your /system/**** folders in your phone and fix the permissions then reboot
Hybrid TW Clock v2.4 SGS3 themed - http://www.mediafire.com/download.php?epc0valgetc4x71
Hybrid TW Clock v2.4 SGS3 themed + Extras pack - http://www.mediafire.com/download.php?s442l1qemcg0cvj
if they don't work you could open the zip and take out the files and copy them across manually to your /system/**** folders in your phone and fix the permissions then reboot