these ones - https://www.dickssportinggoods.com/p/powerblock-exp-stage-1-18pwkupwrblckxpstslc/18pwkupwrblckxpstslc

I'd prefer them just because they're expandable. If you only need something that only goes to 50, I just saw the classic 50s are for sale on amazon for $215 right now - https://www.amazon.com/POWERBLOCK-Classic-50lb-Adjustable-Dumbbell/dp/B00LV09JTQ