You can get a door slab (which is just the door). They generally come without the hinges attached. Some will already have the hole for the knob & lockset drilled but not all. The type of door you want is a bit on the pricey side. It might be best if you hire someone to put in the door for you. Since it sounds like it's an exterior door, you will need to make sure there is a proper sill pan, header flashing, etc to keep water out. Prehung do require more prep (removing old frame) but they are easier to do than having to add hinges, drill a hole in the door slab, & get everything lined up properly. If you had a door custom made to your current door's configuration with the holes already drilled & hinges on, it would only be a matter of popping the hinge pins (assuming the same size hinges are used) and swapping out the slab/door.