depends...
a male rabbit takes up to 6 weeks after the op to become infertile.
so if you get him a neutered female/male then he could be bonded after 2/3 weeks
If you get an unneutered female then you would have to wait the full six weeks. If you go this way though your female is full of hormones and the poor male will be humped like heck (it happened to me, or should I say it happened to Charlie from Autumn!!), this could cause problems with fighting depending on how tolerant he is.
ETA Jill there are a few rescue centres in the NE, you could have a look, some will do the bonding for you (definately a lot less stressful)