Hey
I am searching for the cheapest but still decent Gravel frame.
I used to have a Scott Speedster gravel and am searching for something with similar geometry. But it needs more gusets for travel/bags/random stuff.
https://www.scott-sports.com/global/en/product/scott-speedster-gravel-20-bike
Don't know about the geo but Velobuild GF-002 is cheap and decent with multiple gusets for mounting options. $479 for frame, fork, seatpost, handlebar, seat post clamp, headset and thru axles. Also available from SP-Cycle with a flared gravel style handlebar for a few more dollars.