You won't find much of a market for used stock parts on such a new car. It never hurts to try putting them on CL or eBay. You never know if someone's out there needing to go back to stock for whatever reason. I did that with my stock '14 mufflers, which are around $300ish new from Ford and never heard anything. You could store them so when there's a market 20-30 years from now and people are trying to restore "the classics" you could get decent coin for them. Of course, that's assuming people still drive gas-powered vehicles.
2014 GT MT aka: Ruffian-
3.73 gears, Roush AB, BBR O/R x-pipe, JLT intake, BMR panhard bar, BMR lowers and brackets, FRPP 47# injectors, Lund E85 tune, SR springs, MGW shifter, 416rwhp/393rwtq