Rumors have been rife that McLaren is planning to build a production version of the McLaren Vision GT Concept designed for the Gran Turismo Sport video game. Reportedly codenamed the BC-03, the mystery supercar hasn't even been officially revealed by McLaren yet, but you can already buy a build slot. Listed for sale by Knight International is a build slot for the McLaren BC-03, which you can secure for a €300,000 ($336,589) premium over the car's MSRP.

Sources have suggested the McLaren BC-03 will have an asking price of $3.5 million and $4 million, making it considerably more expensive than a McLaren Senna and even a Bugatti Chiron.

Production will reportedly be limited to just 15 units, so this could be your only opportunity snap up a build slot before the car's official debut as there's a good chance the McLaren BC-03 has already sold out.

Leaked renders designed for a client that emerged last year have shown the McLaren BC-03 will have an extreme aerodynamic design inspired by the Vision GT Concept such as slim vertical LED taillights, a large rear wing, a prominent fin with an integrated brake light , and an aggressive rear diffuser. While the rear looks unlike any other current McLaren car that's in production, the front fascia appears to be inspired by the McLaren 720S as the BC-03 shares similar headlights.

As for the chassis, the McLaren BC-03 is allegedly based on the McLaren Senna. Sources claim the McLaren BC-03 is powered by a 4.0-liter twin-turbo V8 engine and an electric motor that delivers a combined output of around 1,100 horsepower.

If it's street legal, the McLaren BC-03 could rival the Aston Martin Valkyrie and Mercedes-AMG One. McLaren hasn't hinted when the BC-03 will break cover, but don't be surprised if the debut gets delayed since financial troubles recently forced the automaker to cut 1,200 jobs and delay the upcoming hybrid Sports Series.