I'd like a reliable and inexpensive router with OpenWrt.

It's a difficult market though:

- Vast majority people use router provided by ISP. - Some unhappy with ISP hardware quality buy whatever they find online (in my country usually TP-Link devices) - Enthusiasts flash OpenWrt on cheap devices, home servers or buy MikroTik devices (or similar). - Non enthusiasts, but caring about quality and support still have some good (but more expensive) devices to pick from like Fritz!Box in Europe

People wanting pre-flashed OpenWrt will be fraction of a fraction of overall market, so you'd need to charge a lot, which puts you in direct competition with options above.