Those jakks dragon balls look super cool for figuarts
Now for earth dragon balls you can use the ones that come with the chara strap keychains, if you buy a set you get characters with 1 star to 7 stars. i have some and i use them as namekian dragon balls with mini figures. img855.imageshack.us/img855/9494/040pu.jpg
That's the largest Dodoria available so it's your only option. It's HQ DX. It's slightly big for 5 inch scale, but the HSCF is too small for 5 inch scale, so I own the HQ DX instead, as shown in that pic.