Here is a steel transmission clutch spring that came off of a 1986 Ariens ST504 snowblower. See pic.10 for your application. The clutch spring is in good structure with some common weathering and color fade. It holds tightly to the chassis with the included mounting bracket. The spring shows normal contact use, but isn't  badly worn, rusted, or cracked.  It allows for good engagement of the transmission from the hand lever.  This assembly still worked well on the blower, and certainly is handy for a spare when needed.  Included is everything you see in the pictures.  Keep that vintage ST504 moving snow for this season with a good OEM transmission clutch spring assembly!  Please thoroughly clean and lube prior to use.  Please look at the pictures.  Ask any questions that you might have.  Paypal payment due within 48 hrs. of listing end.  Carefully packaged and quickly shipped.  Thanks for looking.