Short answer: Use the Past Simple if it's clearer, and it is a bit clearer here, plus is quicker and more common.
Longer answer: The Present Perfect is usually used in three ways.
Life experience (something occurring in the subject's past):
I've participated in scavenger hunts with members of the Royal Family.
I've never studied Martian.
I've tried to, but I only have one larynx.
A change or action which affects or relates to the present situation:
We've sent you the insects you requested. (They're in the mail.)
I've caught a cold. (Now I'm sick.)
My girlfriend has broken my hip. (Now she hops.)
An action or state lasting up until now:
We've been waiting around all day for that asteroid to hit.
I've never been good at wrestling ogres.
In your example, while all of those Present Perfect verbs are examples of a past action having a result relevant to the matter at hand, it's a little clearer if you use Past Simple because when someone's quickly reading an email the Present Perfect may be less obvious. This is because of potential confusion with the 'life experience'.
If you write '...I've made more copies for you.' it may also be read similar to 'I've made more copies for you at times in the past.' and it's subtly more courteous to the reader to remove the confusion. Past Simple may also refer to the past but the context makes it clear here.
Both tenses are correct in this case and we have a choice of whether we want to speak as though we're emphasizing the events when they happened or the present situation created by them, and I prefer the Past Simple for clear communication. If this were literature, I'd probably use the Present Perfect because we really are more concerned with the resulting situation, unless I were trying to evoke a more vernacular feel.