Before I try to piece something together, does anyone have a decent 5-spoke crank, like a Sugino "Mighty" (or anything, really, vintage/modern, OK) with 48/54 chainrings (or something close)?

I want to upgrade the old Nishiki, but I'm pretty happy with the ratios as they are. I may post this in a "parts wanted" thread as well.

Thanks,
JS