In short, no. Hard to extract, you are talking about several million litres, extracted from the lunar soil to sell at, say $1500 per litre - but nobody needs that much helium 3 right now because we don't have nuclear fusion at all yet. World Helium 3 market is a few kgs a year, a few tens of millions of dollars, just rough idea of the scale.
I'm not sure where to go to get the exact figures. But for an order of magnitude idea, here is an article about whether the US can generate 25,000 litres per year, at a price of approximately $ 1,500 per litre.”
They conclude it can't. So if you were to return 25,000 litres of Helium 3 you could probably sell it at $1,500 per litre right now, if nobody has set up a cheaper way of making Helium 3 by then. But you'd only get 37.5 million dollars from that.
Also, it only costs as much as that because we have a severe shortage of Helium 3.
So, yes, we have a helium 3 shortage and if you did manage to extract some Helium 3 you'd get buyers - but if you flooded the market with a few million litres of Helium it would go right down in price and anyway you'd need to set up an industrial scale mining operation to mine it.
Legal situation is also unclear - do you own the Helium? There are many details and ramifications there as the OST says that resources in space are for all of humanity to use - so - what are the implications there for people who want to sell resources of space to the rest of us? Details are not sorted out yet.
In the future when we do have fusion, if we do - I think no guarantee that it will need Helium as there are several designs being developed.
If we do, then we'd need tons of Helium 3, so industrial scale mining on the Moon. And I'm sure there would be huge debates about whether or not we should mine the Moon in this way, and about who should benefit if we do, and what the regulations are.
And remember - it's not there as a gas in the atmosphere or a well - but mixed in with the rock. You'd need to process about 150,000 tonnes of regolith to get one kilogram of Helium-3