Years ago, when I had a KIA, I used Oponeo for this. After I placed my order, someone from Oponeo in Poland rang me to check the sizes etc. Wheels and tyres arrived very quickly from Germany.
More recently, when I got my Jazz, which had no spare, I used Oponeo again to get a 15 inch steel wheel and corresponding tyre for use as a spare. (Although the car has 16 inch alloy wheels, the rolling circumference of the tyre on the 15 inch wheel is the same. Alloys are porous, steel wheels aren't, so if the spare is needed, it is less likely to need inflation and when I have had a puncture I only use the spare until the puncture is repaired or a new tyre fitted to the 16 inch alloy wheel.)