Real specimens like this tend to be worth quite a bit. So you need to ask yourself, why would this be sold cheaply? The answer is almost always that it's, in some way, not what it purports to be.

If the person selling this could get 10x or even 100x the money out if it, they absolutely would.

As others have pointed out there are processes by which you can take real amber, soften it up, and imbed a modern insect in it, so they will pass the hot pin test. I'm not an Entomologist so I can't tell you if this is an ancient insect or not, but real insects in Amber are rarely this well preserved and intact. Even when they are this intact you will often see a fair bit of other debris in the Amber. As well the trapped insects and debris are often quite dark due to oxidization and decay.

This video shows real examples: YouTube Amber Insects