From these forums, I got a couple of suggestions on Omniracer Racelite bottom brackets with titanium spindles. Saves 100g (roughly 1/4 pound) over Riv's default BB. I hemmed and hawed and finally pulled the trigger (made an online order) on this small, USA-based boutique brand via their website... and...
...six days later there's still no email purchase confirmation (and I neglected to screenshot the original order). I reached out mid-week on their contact form, and the guy replied via his Wix storefront email that he's confused about my "return". I replied that I'm just inquiring about my order/confirmation, and he has my name, city/state, and email used for that order. Really odd that two rounds of emails now and he's still cornfused.
I always try to purchase directly from small brands... but in this case I'll probably have my CC cancel the charge and I'll reorder via Omniracer's Amazon channel. Fingers crossed that the product does better than their retail experience and customer support :-|