What do you mean, matching resistors? You only need a bunch of resistors, and another bunch of double the value. If the standard values don't yield quite what you need, just use two in series to get the doubled value.
2% resistors should be good enough. Use resistors of high enough value that the impedance of each pin is inconsequential. 10k/20k should be fine. Or 12k/24k. Those are standard values in 2% resistors.
Or you could add something like a 4050 CMOS HEX buffer, if you are worried about different pins of the Arduino having different impedances.