Yes, a funeral director can arrange for this. Its just like giving notice to members of the family be sincere and i agree you need to state the purpose of the donations.
How Do I Write A Letter Asking For Donations For Someone Who Passed Away?
You need to clarify why you are seeking these donations and what you intend to do with them in his/her memory. It is usual for the funeral director to deal with this in the death announcement: Donation to X Charity if so desired.