Joe Pichkur on Jericho tpke in Floral Park. I've never had him work on a bass but I've met him and he seems to know his stuff and I've heard good things. There's also a guy in Sam Ash in Carle Place who's good. I can't remember his name but he was the older of the two techs there. A bit ornery but competent. There's the guy at the Music Zoo in Nassau. Expensive and condescending. The tech in the GC in Commack is garbage. That's all I got.
Then there's Mas Hino in the city. He has a great reputation. I don't have any experience with him though.
If you're interested in taking a drive up to Westchester to check out the autumn foliage, I highly recommend these folks. (No affiliation...just a satisfied customer.) The Guitar Specialist