glad you found a kitchenaid
you like, i know you said you weren't really happy with the kd-17 model you had tried earlier. this one will give you the upper spray arm and has an excellent pump! i have heard it said many times that the 18-20 series were the best kitchenaid ever made! i prefer the 15-17 models myself but hey, who cares about that!
parts are def available thru hobart or appliance parts stores. i also recently bought from a member a big box full of kitchenaid literature! service manuals, parts lists, and many "technical service" bulletins from the 50's on up thru the 80's. it was an appliance store's catalog of hobart literature. i do have the service manual for the kdp-20 if you ever need it. i can run a copy for you.
i also have a sales brochure on the 20 series machines and the patricia is outlined in it completely listing all features and cycles etc. i can send you a copy if you would like it!
have fun the kitchenaid way!