I just got some of the VMC barbless, open eye type singles to replace some trebles on a few small spoons and spinners, worth noting if you decide on this type that their sizing is a bit big, their no6 is more like a no4.
EDIT..
I also found some split rings on Ebay from a seller called lurefactors that are only 4mm inner diameter and a finer wire than most, which allowed me to fit some standard (ie not a huge eye) size 6 barbless, eyed, single hooks which I had, to small spinners. they are strong enough to straighten the hook in a pull test. a bit fiddly to fit, and I know perch and jack pike will cope with a bigger hook, but I didn't want to risk the hook point of a bigger hook getting close to a greedy smaller fishes eye when hooked, which can happen. just my thoughts.