The model number is normally found inside the fridge or freezer. You will likely need to remove the salad drawer or freezer drawer to find the model number plate. Otherwise the model number is likely to be on the side or rear of the appliance.
Indesit Fridge & Freezer Middle or Top Freezer Drawer Body Genuine
INDESIT Fridge Freezer IB55 732 W UK Freezer Drawer Basket IB55732WUK 463894
Indesit Fridge Freezer Drawer Middle Large Frozen Food Container Tray Basket
INDESIT Fridge Freezer Drawer Front Flap IBD5517WUK1 IBNF5517WUK C00283722
Hotpoint & Indesit Fridge & Freezer Defrost Timer Genuine: TMDJX06ZR1 C00516868
Indesit Fridge & Freezer E14 LED Long Life Light Bulb Genuine