Did you look online..this popped up for me when i looked 06 gxp backing plate rear.
https://www.google.com/shopping/product/621985534513079812?sclient=psy-ab&biw=1366&bih=659&q=rear+baking+shield+06+gxp&oq =rear+baking+shield+06+gxp&pbx=1&bav=on.2,or.&bvm= bv.99804247,d.aWw&tch=1&ech=1&psi=qtzQVcn6CcmhyATb-LXYAg.1439751355079.5&prds=paur:ClkAsKraX7I083NUCI ct80pAGY26_Y9zmOlQbPk92WIrFYPG2h54FI-qxOMO6-qn-3DBGYOodCMCxAMB_8wbNE5ycTNEgL1ckNUASKauH0Lvrojsh7d PfYk2IBIZAFPVH715iNUJs_0BFsCqLEYPgyHsM7G8TA&ved=0C A0QpitqFQoTCJOCjd-jrscCFQ0LkgodPWcDUg&ei=t9zQVdPKL42WyAS9zo2QBQ