That is basically what I did - ordered the T-Beam initially to have something prebuilt that was easy to get running and the ordered some others afterwards once I had a better idea of what I was doing.
The AliExpress and Lilygo store links are the same device. I ordered the one from AliExpress with the screen already soldered so that it was ready to go and then just bought a battery locally and 3d printed a case for it.