IVF for sterile couple

Dear Rabbi Halpern shlita
I hope this mail finds you well.
I fondly recall our meetings some time again, and take the liberty to ask your assistance.
There is a young couple here I know where the husband is sterile. They would like to have a child with IVF and the sperm from a donor. (the wife is capable of conceiving!)
Can you advise me if there is any heter for this and to whom I can refer them to, who the best Rav would be to consult for this purpose
Wishing you a happy and kosher pessach