The issue with getting two rabbits separately is that some rabbits just do not like each other and will not bond. You have no way of telling till you try. So if they do not get on then you will have to keep them separate, but bunnies need friends so you would have to get them each a friend. Then you end up with 4 bunnies instead of 2.
As mentioned rescues do have bonded baby bunnies if you wanted babies, although personally I like adults as the rescue can tell you more about their personality which is more fixed then. The temperment of a rabbit often changes as they get older so its a bit of a lottery with babies. Likewise with their health and teeth.
To get 2 separate bunnies ready for bonding you're looking at around £60 to buy them(£30 each), £200 for neutering/vaccs, plus 2 sets of housing, so double housing costs lets say £200 minimum per bun. Say £40 for a bonding pen. So for 2 buns it will cost you around £700
For a bonded pair you are looking at £35-50 per bun plus one set of housing at £200, so you're looking at £270-300.
Another option would be to get two baby siblings which you can keep together until they are old enough to be neutered, however you do run the risk of them fighting before they are neutered and falling out, because their hormones start to run riot a while before they are old enough to be neutered. You'd have to be pretty on-the-ball to do this and be ready to neuter asap and separate if there are problems. You'd preferably need to find a vet that will neuter at 14-16 weeks instead of the standard 6 month rule some have.
So basically you CAN do the whole separate baby bunnies thing, but you'd be making life unnessessarily difficult and expensive for yourself for what is the same end result.
Hope this makes sense, I'm shattered and I've had too many energy drinks