Not exactly, but it's very likely a more than adequate drop-in replacement.
The 63xx series boards are the newer X-series design with some improved specs and several significant improved capabilities. I can think of only 1 relatively obscure behavior that I consider *worse* under X-series.
Double-check the specs and pinouts, but you're very likely to be able to substitute seamlessly while gaining some benefits.
CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).