Hi, you can check out Viking Bags, they also sell handlebars, although they don't seem to have a dedicated option for the K75, most of their products are designed to be universal and I think some of their handlebars could be applicable to K75,
When shopping for handlebars for a Brick, first beware that 7/8" and 22mm are
not the same diameter. 7/8" is the larger diameter.
If you order a 7/8" bar, Brick switch gear will not
slide onto it without your reducing the bar's outside diameter first by sanding extensively. If you try to
clamp the switch gear on the bar without doing that, you'll probably crack the housings.
Secondly, you
can find 22mm bars but you must verify that the bar has sufficient length from the end of where the grip mounts to its first bend to accommodate the switch gear on each side. The measurement must be at least as long as that of the OEM bar.