A.R.
You don't have to get rid of the cat M. ~ studies show that people who live with cats when they have a cat allergy are actually over-all impacted positively (health wise) by the antibodies the allergy creates for them. If he is not incapacitated by the cat, keep it!
You can help his allergies by getting a good air purifier (Eco Quest, Breathe Clean or even Oreck carries a good one). An air purifier with an ionizer will eliminate the particulate matter in the air so that your husband can enjoy the cat from a distance, or maybe even up close.
Then a good weekly house cleaning and combing the cat will do to keep the dander out as well.
Many people make the wrong choice by giving up cats for allergies. I am also allergic to cats but have had one or another for 25 years. The air purifier makes it easy to have one ~ and I always wash my hands after I pet her.