All of the parts I replaced when doing the timing belt on my car looked brand new. Idler gears, timing belt tensioner, water pump, thermostat, even the timing belt itself and the coolant. Stupid preventative maintenance.
I got all of the parts, coolant and coolant conditioner from John Gue, a guy I've known for years. He works at the parts counter of Heritage Subaru on the E. coast but they don't charge much for shipping at all. Best customer service from any online OEM parts counter, ever. He'll bend over backward to find part numbers and cross reference stuff for you.
www.subarupartsdepot.com