The cockade is not correct...white with blue ring for Bavaria, not the reverse. If real, the kokarde shown would be worn by someone from IR 96, IIIB Rudolstadt. Helmet seems to have been refinished, very shiny. The markings: Infantry Regt 23, formed 1897, based in Landau. 5C = 5th Company, IIB =2nd Battalion. The dates represent the year the helmet was accepted into Regimental stores. The liner also looks as if it is stitched somehow, I see a row of stitching in your rear visor/markings pic. That is not correct. More and better pics would help. Absolutely everything from the UK or in the UK is suspect I am sorry to say. From what I can see, I would not buy this helmet.