Galley Sink Waste Lines

[CarolaMaster]

Needing to replace old galley sink waste lines as they (welded stainless) were rusted, leaking and below the waterline.

I've tried Trident Sanitation hose and struggled to find fittings that work. WM sells L's and T's but they're too small diameter to seal. Schedule 80 barb fittings from the hardware store are too large, I wrestled all afternoon with them. Are there any Goldilocks fittings available?

I've considered ABS (like a house), but don't really trust the tailpiece-to-ABS connection as it relies on a simple compression nut to hold it all together.

Since I've got a double sink, there are several joints involved. Any thoughts?