It's always disappointing to lose something that you value, especially due to a mistake. It's important to always double-check everything before taking off, particularly when it comes to safety-critical components like wing bolts.
In situations like this, it's important to learn from the experience and take steps to prevent it from happening again in the future. You may want to consider implementing a pre-flight checklist to ensure that all components are secured properly before takeoff. Additionally, you could consider using thread-locking adhesive on the bolts to provide extra security.
If you're looking to replace your 3DHS Extreme Flight 60cc electric, you could consider looking for a used one online or reaching out to hobby shops or online retailers that sell remote control airplanes. Before purchasing, be sure to do your research and read reviews to ensure that you're getting a quality product that meets your needs.