I got my new tyres at hlaf the price of dealer prices - Mini Rubber cheap tyres my arse!!! Try shopping around a bit - but i guess if it's a fast puncture then your kinda stuck but if its slow then you can afford to wait for a next day delivery to likes of Kwik fit.
Could be worse - i had to shell out for a new alloy and tyre 4 weeks after i got my car - the council lft a kerbstone sticking out of the verge after some road works - very interesting feeling haveing your tyre blow out at 50 round a bend!!! That said the Mini emergancy service were amazing - they ent out a car with a spare and arranged my loan car and everything - at 7.30 am!!!