G’day…I had the same problem in finding a good quality mag chain in 1/2 x 1/8 and settled on a pack of IZUMI brand that is prefered by the offroad BMX nutters ! It was $29 compared with around $15 for crap bicycle chain and so far has performed well with no re-adjustment needed. This weekend is the Australian section annual gathering so it will get another serious test ! 🙄
Good luck
Peter Scott, Seacliff , South Australia