richie is totally right, thats the core stuff, but if you're contemplating making your 1300 into a 'normal looking' sprint, then the dash is different, the badges, if we're talking standard then the steering wheel (or at least the rubbery boss cover thing), front wiring loom, dash wiring loom and also the rear end trims are different too. square headlights vs twin?
1300 also doesnt have wood door cappings, and also the seats are a la toledo I think, i.e. a bit less wide.
anything else... errrrr, not sure if boot light was standard on 1300, but glove box light isnt.
the core stuff as per richies post is what you'll need to sprinterize it, along with engine bay wiring loom, subframe, gearbox tunnel and zorst. I'd also be wanting to upgrade the springs n shox. sprint front brake pads are meant to be a different compound, and the drums n shoes are also different, i.e. wider/more friction surface.
1850 is a lot closer to a sprint but all the drivetrain will still need to be transplanted.
i'd just buy a sprint!