i will give you £100 for it
As it has no tax or MOT, but a moderate mileage, and it's a pre facelift, I would pay £200 for it.
at the end of the day its a car with no tax or mot, so it will only really sell for scrap value, unless it can be proven to be mot'able, but i always think if someone says to me im selling my car its got no mot but it will pass one, i think why not get one on it then for the extra £40 and get the extra £2-300 it will be worth?
if its as you describe its worth £150 - 200 imo