It surely looks like a 107 mark from these pictures. But as you say it does not have the expected back hardware of a 107. Maybe its a rarer variation?
Lets see what the other says.
what ever its original
107 it is. Here is a list of makers of hollow badges that feature integral hardware, courtesy of WAF.
Look at post # 107. I didn't have time to post this for you this morning.
Wound Badge List of Makers. - Page 8 - Wehrmacht-Awards.com Militaria Forums