The NUTS that fit the blades are M2, Du-Bro makes packages of METRIC hardware available at most LHS, check the R/C CAR areas. As far as your blades, I would recommend PLASTIC blades, they are almost NUKE-PROOF. I use the ones from Helidirect, HDX plastic trainer blades (flat bottomed #VTS-109W), symetrical blades also available for about 12 bucks!
Don't buy the stock tail boom! Go to WALMART & buy 8mm by 14" knitting needles (they have the same purple color), 2 needles for 4 bucks, smoke'en deal! Cut the tapered tip off, cut the head off, deburr ends, drill or ream one end to 7mm (.2755"), cross drill hole for tail-motor mount & your done, other than installing the wires to the tailmotor & mounting it.
The knitting needles are twice as tough as the OEM ones, blade strikes leave scratches, and it doesn't affect the balance!

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