I cannot give you advice on where to buy a Norton, but I can tell you that the unevenness of your honing results are not due to your narrow hone. The majority of the seasoned honers at SRP do X-strokes. With many razors, X-strokes are even imperative for consistent results.
The Norton 4K/8K has an outstanding reputation, and I'm not saying it isn't worth buying one.
I'm merely implying that a hone that's 2 inch wide, or even 1 1/2" is not a reason for uneven bevels.

Best regards,
Bart.