Been doing some research...
The Bendix site has a ton of great info, this is the closest rotor I could find to the measurements I took off the Slingshot rotor.
2006-2014 Mazda MX-5 Miata front rotor specs:
Diam. 290mm 298mm
Height. 45mm 45mm
Thickness. 22mm 21mm
Discard. 20mm 19mm
Center. 72mm 68mm
5 bolt. 114.3 114.3
Rockauto has drilled / slotted versions for $40 and up each... stock at $20 and up each...
Not telling anyone to use them, just sharing info