What I did was buy some really simple black boots from payless. You might be able to still find some there (even try Ross, TJ Maxx, or marshels). I bought some black straps that were similar to the material the boots were made out of. And then, I hand sew them on. Also hand made the skulls with a pin in the back to pin it on to the boots.
Total costed less than $20
Natsuo, Misa Amane, Amu Hinamori, Alice, Chrome Dokuro, Eureka, Akane Tsunemori, Sasuke Uchiha, Karuta/Riri, Monomi, Aoba Seragaki, Fem!Noiz, Heroine (Amnesia), Love Colored Ward! Luka
Nonon (50%), Sei (95%), Fem!Trip (0%)
: SacAnime W'15 (Ririchiyo/Fem!Trip/Aoba), AX 2015 (planning)