Can you still get gender selection even after a vasectomy?

I have 4 boys. I love them dearly. I have always wanted a girl. After my fourth, we decided for my husband to get a vasectomy to further my career and his. It's been 3 years and I am ITCHING for a girl. I see little girls everywhere and get so sad. Don't get me wrong... my boys are wonderful and I love them no matter what. I just want a girl so bad. Now that my husband had his vasectomy, he is not wanting to undergo a reversal. I have researched Microsort and am trying to find out if we would still be able to have that girl we have always wanted. Can they retrieve sperm from my husband by needle or something and still do the microsort? Has anyone ever heard of this being possible? Please don't judge me by wanting a certain and that "I should just want a healthy baby bull". You would not understand the situation unless you were in the same scenario. If you had 3 or 4 of the same , you understand. Thanks.