Dougg, I have seen a few of the older Trinity swaybar kits lately. I have to agree with Eric, LosiBK2.com & 4wdrc.com are really good sources of information on the XX4.
Oh, and being an avid eBayer....the e mail you got was called "phishing", it is actually sent from someone other than ebay with a fake link hoping you will "log in" with your real ebay account (if you had one) onto their website, then they have your user/password and start wreaking havoc.
Ive never had to use the rear swaybar on my xx4, I think the car rotates well and turms smooth/sharp enough for any track I have set it on.
--Joey -- AtomikRC/Venom Batteries
Old School Racer, Vintage RC Car nut
AE: RC10 (X4),B2,B3,B4 worlds,B5,B5M,RC10T,T2,T3,T4,T5M,B44.3,SC10
BSR BZ-444 pro,TRX3,MK1 Kyosho Ultima