Can anyone recommend a good mixer for prune juice?

I have acquired a gallon of prune juice and I’m hoping to introduce it at the next party as the “New Thing I saw on TikTok that you guys totally gotta try”. I did not see it on TikTok, I raided my grandmother’s pantry for expired goods.

I want to make this party a blast. I am also of the inclination that any money spent on mixer could be spent on more booze.

I will not be partaking, I quit drinking months ago. That means I have no method of telling whether my mixture is a banger or not.

Any ideas?