Screw holes to secure bottom plate stripped, what to do?

I recently replaced the hdd of my Mac Mini with a SSD, but unfortunately the somewhat fragile screw holes to hold the little roster with the wifiantenna, which also secures the bottom plate got stripped.

My first though was to use bigger screws, but then the bottom plate will probably not fit anymore, as the lock system needs the exact same size screws.

Any ideas to fix this problem?

Right now i used some tape to hold the little screws in place, but this is a poor mans solution and will not hold very well in the end, especially when i have to open it again for whatever reason...