Hi Footloose, sorry to hear about the scratch. Motability will probably tell you not to worry about it, but if it bothers you I’d opt for a smart repair, £80-£100 is probably about right for the size.
T-Cut is probably a no go, if you can feel the scratch with your nail then it will be useless. You also run the risk of over polishing the scratch and making the paint work a different shade. My opinion is smart repair if it bothers you enough.