You may want to check out the Ultimate Slow Stick thread at
www.rcgroups.com. It is a rather gigantic thread--in three parts at that--and will likely tell you more than you wanted to know. You'll find it in the beginners training area. If you can't find it, let me know and I'll get the link.
As far as parts, I know they are available. I don't exactly know what you need but look in motor accesories at
www.backyardflying.com.
Haven't shopped here myself, yet.