for the YZ pegs i used the oem springs from the YZ and the Pivot Pegs springs came with it also ..
for the DRC pegs .. not sure but it seems like look kinda like my YZ pegs .. you might check with Wheeling Cycle, they carry DRC hardware and sell option springs for the WRX/R http://www.wheelingcyclesupply.com/shop/4/11/index.shtml