I wouldn't risk getting her. Allow me to explain why. Intact males aren't likely to form a solid bond with any other rabbit -- male or female, fixed or not -- because their hormones will influence their behavior.
But even if your male was already neutered, it is important for him to choose what other spayed female he is willing to accept. He has to be the one to agree to get along with his potential bondmate. Just because two rabbits are fixed is no guarantee that they will get along.
So, what if you do get this female? What happens if they don't get along? Then if you go through the process of getting him neutered and then waiting out the 6-8 weeks after neuter for hormones to settle, and then beginning the bonding process, then what? What if they still refuse to bond? By then you will have had the female for a while and won't be able to return her. Then you're stuck with two rabbits that still have to be housed separately (separate for the next 8-10 years) --that's the risk you take by getting this spayed female.
The better, risk-free option is to wait until a couple months after your boy's neuter to begin looking for a potential bondmate. When that time comes, check rabbit rescues (as opposed to generic shelters). Rabbit rescues typically have many rabbits and they are all fixed. They allow bunny dates to pre-screen for potential compatibility. If you take one home and it refuses to bond with yours, then they typically allow an exchange. In other words, they work with you to ensure you wind up with a compatible bondmate.
That would be the recommended way to find the right bondmate for your boy. He has to be the one to do the choosing.
(If you list your state, we can find rabbit rescues there.)