Yeah purple is definitely a solenoid, I remember replacing the copper washer on my 25, Not sure what the other bit is but I'd imagine it's probably the part that actually moves to open and close the AAC valve, from memory there's a spring inside that area. Manuals and FAST don't go into any detail about what's what because you're supposed to just replace the whole unit when it breaks instead of fixing them
Nah they're not origin, 01 have spokes that curve at the ends like TE37's and 02's have spokes that run flush with the lip. Those have spokes that run into the dishy area.