I have rented a hydraulic flaring tool for job requiring many 1" T316 stainless tubing. They normally have several for in house use as they make hoses for people, and a lot of them terminate in flare fittings. I'm sure any place that makes hydraulic lines would do the job for a small fee. Often tractor and heavy equipment service outfits make hoses and could do it. That is, if you don't have other access to a larger flaring tool.
Ann L will do the job. It won't require a double flare like brake lines. As an alternative, you could consider compression fittings if flaring presents problems.