don't get cx forks!
there should be plenty of steel audaxy road forks with rack and guard mounts around that are not that much longer than than the ones you've got.
longer blades and more rake will affect the handling, and so will a rack with a load. but none will render the bike unrideable.
There are/were some Roberts forks on ebay that would be suitable.
There are/were some Roberts forks on ebay that would be suitable.