Rolling stock wheel dimensions?

[Flare]

I'm building an On30 Porter tender and would like it to have spoked wheels, the Thomas line looks like a good source.

I need the wheels to be 24" in 1:48 scale, are there any wagon or coach wheels that might be large enough?

[Kemptown Branch]

The standard wagon wheel should work for it. Its 13.5 mm in diameter.

[Flare]

My math says that's nearly half an inch larger than the prototype.

Close enough for me.  Thank you.