I forget the exact thread pitch, sorry.
It's a weird funky size, nothing that Home Depot or Lowe's carries.
Ace Hardware may be able to assist, though; they usually have more of a variety.
Napa Auto Parts also has a more detailed thread finder chart.
If you're looking for lug nuts, I'd recommend stopping by a junkyard. They can't sell them to you, (I guess liability reasons?) but they won't complain if you grab a handful. I just used the existing lug wrench in a wrecked T4R and popped a few off and the guy didn't care one bit. They'd be scrap soon, anyways.
You'll be hard pressed to find less than a full set online, and AutoZone/Advance, etc charges out the ass.