For the sake of current and future peace in the relationship, I'd get the things out and send them off to her.
Where does it end, though? This route just seems like the beginning of Ex constantly demanding things that she left in the house 3 years ago and getting them or throwing a hissy fit because she doesn't. "Here, Ex, let me bend over backwards for you just to smooth things over even though you're a demanding, special snowflake of a person!" I don't think giving in to her demands is a good idea at all.
I think if you are willing do to some things it's easier for all to understand when you won't do other things - if that makes any sense. These relationships
can be so difficult that I find it's best to try and give as much as you can. That way, when you are unable to comply to a request, there is no suspicion that it's for any other reason than what you give.
Hindsight really is 20/20, which is why when I see a situation like this, my advice usually leans toward doing whatever is necessary to keep peace and harmony between everyone. It just makes things so much nicer and so much easier on the kids.
I can look back at my relationship
with my husbands ex and see plenty of oppurtunities where I could have made decisions that would have made the relationships
between all of us more pleasant. For the most part, things were ok, but they could have been better. Looking back, I can see that I could have done more to make the situation a happier one for the kids involved.
Just my opinion from my own life experience.