System/staff text containing beamed eights, triplet

Hello!

Thanks so much for the helpful community - I've been searching through it heavily and found many valuable solutions.

Per the subject & screenshot, however, my most recent attempt has thus far exceeded my googlefu skills; I've not yet found an answer.

While I think I've figured out how to insert the beamed eights via the "Beamed group of notes" symbols, the triplet w/bracket has eluded me. Can anyone suggest how I might be able to notate this?

Thanks so much!