$600 is a bit 'pricey' for any Kent kit. (Just my opinion) However, I will say this, if that little kit was made in New York and it has aged maple shells, and if it could be had for $350., then it would be worth buying and paying for new vintage round-over bearing edges. You'll end up with a good sounding set of drums.
At $600. I'd give it a 'pass'. For that money there are (player) vintage Ludwig kits to be had! Wait, 60's New York factory Kents in similar condition come along -for much less- fairly regularly. Patience wins the deal of the day.
John