Gedenk medalle

[plumbob]

Hi guys sorry if I’ve put these in the wrong place.
Please could you help me with this medallion I have been offered, never seen one before but, I cant seem to find out much about it, and need to give the seller an answer by tomorrow night.
Just the usual questions like how can i tell if its real and is it a commemorative medal and when were they issued, sorry if it seems as if I am being lazy on these ones, its just that I could spend hours trying to research these. Which I will be doing anyway but may run out of time, So I am hoping one of my friends on here can help.
How much should I offer?
Thank you in advance
Rod

[Adrian]

Never seen one before or heard of these Rod so I'm not much help. I'm guessing it's a post war piece as the date 1945 is on there. No-one knew when the war would end before it did.

There is also the absence of a swastika on the badge, again, pointing towards post war production.

I like the Destroyer badge image though.

[plumbob]

I thought post war as well Adrian perhaps in this case a commemorative medal for those in the kriegsmarine. It would be nice to know if they even existed or when they were given out.
Thanks
Rod