OS Service for custom ROM

Is there a service, where one could mail-in their devices to have a custom OS installed?

I have three, dated android devices that I would like to have updated with a custom ROM such as MSM-Xtended, PSOP, or corvus to extend their life.

And no, I do not want to simply discard these devices.

I have modern phones for my day to day and I keep these around for different functions.

For instance traveling (dual-sim), plug-in tools that only work with specific receptacles, and just because I like having them.