If you really want to farm it, then create an alt account solely for spawning raid bosses. Befriend only yourself and only send help request to friends, that being just you. Deal enough damage to MVP and then send help if you can't solo/dual it yourself. Don't waste your resources on your main account for them. Now that we've had our first raid event the other week, we will now have raid and advent events alternating every week and you will want the recovery items for those, not some easily replaced SR eidolon that's less useful than a R eidolon.

The only point in farming raids is for exp, SR weapons and daily missions.