Your best bet may be to work out your requirement in total copper area in the usual way, and then contact the wire manufacturers to see what is available or in stock.

No real need for wire tables, because if you work out that say 10mm ^2 is required, then 10x1  or 5x2 or 3.3x3.3 will all work, but one particular shape may be easier to wind. Some sizes while listed, may be more difficult to obtain.

Zacky,
Here is at least one. . . .

http://www.mwswire.com/square.htm

NEMA Standard MW1000 defines standard sizes for magnet wire.

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