I don't have info handy but Lundy is shown in Navbox as 200m grass.........
One may as well talk about taking a TB20 into a heliport. It's not really applicable.
The acceleration of any 250hp aircraft with a VP prop is obviously going to be very similar, and if it has a decent cruise speed then it's stall speed in landing config isn't going to be far below the certification requirement which I think is 59kt. The takeoff speed is going to be similarly related. A max perf takeoff Vr in a TB20 is about 65kt.
I've been to 500m (LSPV) and that is quite close.
To operate a 1400kg plane with a 65kt Vr from 200m with a conventional takeoff technique one would need about 500hp.
Or else do a soft field takeoff where one floats in the ground effect; a TB20 would get "airborne" in about 150m but I would not do that unless absolutely desperate, and anyway one would need the extra distance after the runway. Why take the risk?
Why is Lundy relevant to a TB20 discussion?
I've PMd the OP with some details.