Albeit in Canada, here are the best sources I've found North of the border:
http://www.rocketrally.comhttp://www.rallysport.cahttp://www.pdm-racing.comWithout question, Rocket Rally is going to be your best prep shop in Canada - particularly for Subarus(but, they do Lancer's as well). It is
run by 2 time Canadian and 2004 Canadian, USA and north American Champ
Pat Richard. He has access to DMS suspension and all the bits you may want. They'll even build you a fully-prepped Rally car, starting at $8,000 CDN($6400 u.s.) :)
Granted the above sources are more geared towards Rally racing, but, the racing guru's are without a doubt, the best source of information and products. If you find any others, let me know.