I couldn’t find any verified or safe source specifically for offering Khmer font downloads. In fact, selapa.net is not a known, reputable font repository, and it may pose security risks (e.g., malware, misleading ads, or unofficial font packages).
If you need a specific Khmer font style that you think selapa.net claims to offer, tell me the font name – I can help you find the for it. selapa.net khmer font free download