[Sylvester Stadler]

58286 is the Field Post Number of the SS-Panzeraufklärungsabteilung 12, the commander of which was Sturmbannführer Gerd Bremer. This unit is the equivalent of a reconnaissance battalion. The abteilung consisted of six companies which includes the headquarters company.

I have consulted the book by Hubert Meyer, Chief of Staff of the 12th SS Panzer Division, The 12th SS: The History of the Hitler Youth Division, in two volumes in English and the German edition, neither of which mentions the two men about which you inquired. I would recommend you buy the book, available in paperback if you are interested in this division.