Sante? As in, fitted with Shimano Sante components?

If so, it's 7s, so hopefully you bought 7s levers. If so, you're good to go.

600 Ultegra (6400) is a good substitute. It came in 6s, 7s and 8s IIRC. Before that it was just called 600 (can't remember if there was indexed 6s or just friction), and after that it was just called Ultegra.