If your search for has failed, don't give up. Here are free or cheap alternatives that cover the exact same A1 content:

VDOC.PUB offers a direct download option for the first volume.

Luxembourgish ( Lëtzebuergesch ) is more than just a language—it’s a key to integrating into the Grand Duchy’s society. For newcomers, achieving A1 level is often the first milestone, especially if you’re applying for citizenship or simply want to greet your neighbors with a confident "Moien!"

The INL offers official downloadable course descriptions and sample exercises for their A1 courses. While not a full textbook, these PDFs show exactly what grammar and vocabulary you need.