Okay, I've made a Yoko cosplay most of the way, so here I go, trying to help (you can see my Yoko in my gallery):
1) For the boots, you can find decently cheap pairs of White gogo boots (I found some on amazon), and paint flames on them. (If you don't have the option to buy online currently, try local shoe stores and garage sales) As for the zipper, I'm still working on that myself...
2) The bikini top, okay, the first thing you need is a random bikini that fits you. Then you need the fabric (for my Yoko top, I used a black swimsuit material for the main part, and a red cotton shirt for the flames, some people use PVC). Take the bikini top that fits you and pull it off the bottom string, place it on the fabric you're using to make the Yoko top (Just be sure to have it flat, you need the same size material). Trace around the fitting bikini top piece and trace around it (leaving a little extra space for where you have to hem it), and cut it out. Do the same with the other side.
Now make sure you don't put the flame pieces on until AFTER you finish the black. It will make it look wrinkled and bunched up if you do it at the same time.
For the flames, You will have to trace the full triangle size/shape onto the red, draw the flames inside the triangle where they are, and then cut them out, then sew the red onto the black.
For the sewing, please reference this tutorial I used: http://www.threadbanger.com/post/999...f-old-t-shirts
3) The tights. Okay, I highly doubt Walmart has them right now, but I bought mine last halloween at Walmart. The only difference I found between those tights and the ones Yoko wears, was mine had little bows on them, and all I did was cut the small bows off and they look great! If you have the option of looking online, try amazon, they are Opaque Pink Thigh Highs, I believe.
4) The Prop: I LOVE THE IDEA FOR THE FLAG! Such a good idea, cause I don't think I could make the rifle either!
I really hope I helped, but if you need further explaination, please, don't hesitate to ask!
BTW: I love that you're doing Yoko even though you're not super skinny!!! GO YOU! <3 And hey, you got the boobs! Most of Yoko's cosplayers don't! (Me included, lol!) Best of luck to you!