New sprocket with old chain

So I got a fresh wr250r with all new stock parts. I want to upgrade the sprocket to a 47 tooth but I only got less then 2 miles on existing parts. So could I buy a new sprocket and add some linkage to the existing chain and be alright? Or do I have to get a new chain aswell.
Thanks

Less than 2 miles on the chain? I'd be comfortable replacing the sprocket and using the same chain. I doubt it's been stretched and broken in that much in so little time.