Re: seriously, only a cloth diapering stay at home mama's dilema ;) (stash??)
For one child you have plenty. If you have dozen or more wool I think you should be fine on covers too. Just make sure all 12 don't need to be washed as once... that would be pretty lazy-- don't covers easily go 3- 4 days or longer between needing to be washed?
Best thing is try it out and see what happens.