Making the box for my Italeri Gigant glider with sheet styrene was a bigger project than I expected.
Visit the grooming section of your local store. Look for the little rubber bands that are used for ladies making pony tails. These rubber bands come in a variety of colors and sizes all in one small bag. The rubber bands are so tiny they can fit almost anything. They are also so cheap, you can cut them off rather than pull them off. One bag usually lasts me for years, even decades. The other rubber bands are for orthodontic braces. Very small rubber bands that are also very strong.