One of the few shops in Germany that sells ecclesiastical workwear is the clothing shop formerly known as "Polykarp Reuss" in Cologne, where I bought my first collared shirts. They were of such high quality that I can still wear them today after 30 years. The shop is now called "Paramente Schmitt" and also sells books. Thankfully, not only the online list, but also the shop window has my book "Altar and Church".