This diorama accessory set from Royal Model is available directly from  Hobby Link Japan.

These unpainted 1/35 German WWII Jerry Cans will be a perfect item to add to your vehicle or diorama.

You may be required to fold the photoetch in this set, but if you have one of the Hold & Fold photo etch benders from The Small Shop, then this will be an easy process.    They have a variety of benders for sharp corners as well as rounded corners and in many different sizes.