are you doing the yellow/gold contacts for her eyes? having a wig with a blue tone to it will make yellow stand out a lot more against bluish tones since they are somewhat opposite warm and cool colours.
a silver/white wig will be easier to find but then you get a flat tone that may wash out your skin tone a lot and you'll need to compensate with blush/bronzer a little more when you do make up. you will have silver hair and gold eyes and look colder and harsher than if you had gone with a bit of colour to the wig, even tho that colour is blueish.
it's also better in pics, especially ones with flash, to have a bit of colour tone to the wig than none at all to keep from being just a big white blur and making the contrast too low to pick up any nice details in the pic. it takes more adjusting for me in photoshop if a character has white or silver hair and a white shirt or outfit than if there is a bit more colour there. the hair ends up looking on the blue or purple side when i adjust it to get more detail to show up anyways.
does this help you a bit more?