Well, 10 raids a day doesn't take too much time tho. You can just auto it while you sleep and do the raids when you have time. By the end of the week, you'll get to Lv 70 (or maybe more, considering the first 30 lvs are quite easy and quick to finish)
A +3 only requires 15 recipes. For a plus +5 you need 63. If you want to split it evenly till the event comes back (+4), you’ll need 31 recipes. Unless for some reason this item needs more than previously released items.
if you can't finish the raid in one run everytime, you have to clear 10 raids with at least 20 tries. and with the stamina cap at 5 with about one stamina regen per hour, meaning we need to prepare quite a lot of time to clear 10 raids per day. that being said, i think collab event raid should be easier than usual raid, just like death machine, so maybe it's worth it.
This farming is very time consuming especially on early level. You got a very few amount of coins after all. However it is gonna be faster to farm it the higher your raid level is. If you really want this stuff it might be wiser if you grind it ( for example in your free time today ) till you can't end it in one run, and then take it slowly till the end of event.