Just go back through the Serpent Temple and collect the idols - they should still be there. IF they are truly gone - do you have a save from before going to the Temple (SAVE OFTEN in different slots!)?
If you don't have that, resetting the game isn't a bad option. Your characters are more powerful and should breeze through the early part of the game. You will only loose QUEST items, the rest of the stuff you keep!
Wyv