Well, I grabbed an MSI Ventus GTX 1660ti for $269 @ Walmart.com, of all places. Sold by Walmart. Probably drop-shipped by MSI directly, who knows. Hopefully, Walmart's warehouse minions won't screw up the order and send me a regular 1660 by mistake, if they're not drop-shipped.
That was about the max that I could afford. Couldn't really find any RTX 2060 cards for $300 or less at the time.
Edit: Also grabbed one of those Sapphire RX 580 refurb cards that Newegg had for ~$125. I don't know how many that they had, but they sold out rather quickly. That's for a build I'm working on. Hopefully, maybe I can get $600-700 for it. (Ryzen 6C/12T CPU, 16GB RAM, 256GB M.2 NVMe SSD, have to still add a HDD to taste for the purchaser. Also has decent RGB bling-bling.)
Edit: I just checked Amazon.com, same price on the MSI Ventus GTX 1660ti, maybe Walmart was price-matching them.
Edit: Got the MSI Ventus 1660ti installed. In the top slot, with an RX 470 in the bottom slot, temps have stabilized at 85C for the 1660ti, and 73C for the bottom slot for the RX 470. Mining-wise, they're not too different, I think that the Ventus is thermal-throttling, to maintain temp limits. Around $0.27/day, with bursts for the 1660ti to $0.33/day.
Power-wise, at least according to the NH profitability calculator, the 1660ti makes around $1-2/mo, after electricity costs.