depends on load rating, speed rating of tyres.
Correct load ratings can start from about $250 a tyre.
Tyres which are about 83 load rating can start from about $170 a tyre.
Rims on the other hand can vary from style and brand.
$200-$600 per rim.
Tyre and rim package usualy go for about $1800 fitted.

Tyre shops can pay as little as $90+gst for a 215/35R18 tyre.
They pay from wholesalers about $110+gst for a cheap 18 inch rim.
That can give you a idea on how much you can screw them on price.

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11.1 @ 127mph