I simply say contact list or call list, as in I have a dozen donors on my contact list for the weekend or We have 600 alumni on our call list for the campaign. I am not familiar with any other term that refers specifically to a list of names to be contacted in the short term as part of a task list, though you could refer to calling the person as a task:
I have to remember to contact Sarah sometime this week about the party. I'll add calling her to my to-do list.
In fact, I don't see what is wrong with to-do list, if it is understood that the person named is to be called.
We've been calling everyone in the membership directory. Abramson through Lynd are done. I still have Mabel through Zukow on my to-do list, though.
The other suggestions either refer to a comprehensive list of contacts (e.g. address book, Rolodex) or documents or systems that do not necessarily involve contacting anyone (e.g. planner, agenda).