Home offers bobber kits that will accomodate your request if you're leaning that way. Or you could go with a trailer fender and home-made bracket supports and adapt a sprung solo seat yourself to get the same look. $$$ all depends on how creative of a craftsman you can be.
On the other hand if you're simply looking to change the style a la full valanced fenders etc, find a boneyard and bring your tape measure for starters.
the questions:
1> If you can leave the suspension and brakes closer to stock you won't be affecting safety. Front brake removal and hard-tailing is where this issue comes into play...not to say hard-tailing is unsafe but it won't corner like it's supposed to so you'd have to tailor riding habits accordingly.
2>
Jack's Rebel Warehouse - Rebel Catalog, Honda Rebel parts and accessories Jack is in Florida (vicinity of Orlando)
3> depends what you want to do, I've done most of my Rebel chopper with a $1K budget but I could have easily gone with a $5K budget too...