Her orange is a mix of Barnacle's neon orange and the basic white, and her pink and purple match G3 Rainbow Flash, Sunny Daze, Pink Sunsparkle and the like. I don't know if her purple was originally warmer, though; this needs a bit of explanation.
My childhood Rainbow Flash and Baby Romperooni have unsalvageable rotted hair which crumbles all over the place whenever they're handled. I was really frustrated as a child, since Rainbow Flash always had frizzy hair. It's not financially worth it (hair costs more than decent replacements), but I want to reroot them for sentimental reasons. I've gone through and matched them to various ponies in my collection, which I use for further matches since I don't want rotten nylon flakes in everyone's hair! So Romperooni has white and the same pink and orange as Rainbow Flash, and all four of Rainbow Flash's colors match Sunny Daze (at least II and III).
I found Sunny Daze III after Sunny Daze II, and noted that III's purple was warmer than II's. I magnetted them to the breaker box, which was in my old room. I'd forgotten which was which (in fact, this is just an educated guess) and compared them... and to my surprise, the purples were the same! I've never really been a morning person, and that's when a sliver of sunbeam would shine directly on my G3s, fading the warmth out of the hair... Oops. Well, now I know!
So the G3s with this color, I assume, all started out a bit warmer, but the warmth fades out. Differentiate this shade of lavender from the slightly iridescent one on the Ivy beanie.
Here's a list from memory of matches and non-matches for her non-orange colors. I might come back and add to this later.
Pink:
Spoiler
Matches:
Sunny Daze
Baby Pink Sunsparkle
Sparkleworks
Rainbow Flash
Romperooni
G3 Petal Blossom
Probably G3 Rainbow Dash
Non-matches:
Tangerine Twinkle (warmer, lighter, and a bit more neon)
G1s, such as Heart Throb (too dark/dull)
Purple:
Spoiler
Matches:
Sunny Daze
Rainbow Flash
Baby Pink Sunsparkle
Non-matches:
Tangerine Twinkle (Too cool and too bright)
G1s, such as Baby Glory (too warm, light, and dull)
Ivy beanie (a bit darker, with shifty colors depending on angle of light)
Unfortunately, I'm clueless about how to crack her open. I'd be scared to try, since mine's been through enough (the seller shipped her without bubble wrap, knocking out an eye gem that I did end up finding and gluing back in)!
Are the eye crystals in yours white/clear/silver, or is that a pic from before they were replaced? Mine has dark pink!
Also, are you sure her mane is missing hair? On mine, you can kind of move the hair around in its toothy gap thing, and sometimes it likes to recede a bit!