HI - i got some off ebay - just type in OPK in search bar and that should guide you in right direction. I think i bought 20 for about $24. PRetty cheap !!! I found 20 more than enuf. I just tested 2pm every arvo during my fertile window - i didnt ovulate till CD25, so i went thru quite a few during this cycle....but hey, i got a , so i totally recommend them....

HTH