Where can I find suitable replacement tubes for Wehrmacht equipment and historic military radio technology?

For Wehrmacht equipment and historic military radio technology, the correct type and a technically clean selection are especially important. Tubes such as RV12P2000, RL12P35, P800, LG1 and T15 are particularly sought after here. The RV12P2000 was used as a versatile army tube in many devices, while the RL12P35 was used as a 35-watt transmitting pentode in the shortwave range. Types such as LG1 also explicitly appear in test and radio technology of the German Wehrmacht. Anyone who wants to preserve or restore such devices should therefore specifically look for suitable and tested tubes for the exact respective device.