Yes it would be possible to write a C wrapper for my Rust library and link that from Node, however I expect you might lose a lot of performance to data conversion.
I have yet to do the regex engine port, I'm doing that later this evening. I'm porting it from Oniguruma to https://github.com/google/fancy-regex which accelerates common types of regexes using the awesome Rust regex crate which is super fast.
You can very easily export a C api from rust. And fact you would have to if you wanted to write a wrapper anyways so I think the wrapper is probably unnecessary.
And, do you have an issue for the regex port? Would love to see the benchmark.