Question re WAAC and QMAAC cap badges

[Home Guard]

I found this listing from a dealer discussed in another thread and do not buy form him, however it helps with my question. To be clear I am not wanting or planning to buy this.

My question about the WAAC and QMAAC cap badges is the solid fill ones, are they a valid badge? If so, how can you tell if it's a good one and not a re-strike or fake?

https://www.ebay.co.uk/itm/WW1-QMAAC...AAAOSwBrReG4hG


If it is a good badge then I will want to pursue them from reputable people/dealers.

Thanks,

Terry