I ran into a guy about late spring and I could tell he was on a bike from his clothes etc. After inquiring he said he was on an electric bike, rode quite a bit of miles and loved it. I mean this guy couldn't have been happier with his new ride. He showed me pics on his phone. I'd estimate he was around 60 and he didn't really look like the biking type.
Long story short for your question is he custom ordered it from a company in Huntington Beach. It wasn't cheap but it does have lithium batteries. Plus he was able to get it in the color he chose. The "wasn't cheap" isn't the worse thing either because as he was describing the bike, I was surprised it was "only" $2,500. And the good part about that is, it might be expensive enough to be generally available. As opposed to a bicycle being in the $1,000 + or - range; you can basically forget it for who knows how long. I think he said it took about 4 months to arrive after he ordered it.
I know you mentioned you were a cheapskate but it seems there's definite value. Plus I knew a guy that bought a lead acid electric bike for $600. I wouldn't have wasted the $600 on it.
Anyway it would be a relatively local purchase. I don't remember the company name but if you look for custom order electric bikes in Huntington Beach I'm guessing it would be fairly easy to find.