Originally Posted by
bargainguy
https://tribebicycles.com/products/drop-bars
Tribe makes a 22.2 mm drop bar with a 25.4 mm stem diameter. This lets you run MTB shifters and brake levers on a drop bar with 25.4mm stem compatibility. Not sure if this is the type of bar you're looking for, but it's an option.
Unfortunately, these people seem to not be in business anymore. The "cart" is disabled and the phone number is disconnected.