I really dont understand you guys. You are asking for 20-50-100 nike proxies and you are doing it WRONG.
nike is blocking/banning ips as they are allocated by ARIN or RIPE etc ...
If on ARIN there is a /24 (256 ips) allocated to provider x and you get 50 proxies from those 256 then all proxies from that subnet will get banned/blocked even if you dont abuse the 50 proxies or even if you dont use them at all you will still get your proxies banned cause other proxies from that prefix are allocated to other nike users.
lately nike is not banning access to their website, they are blocking the adding to cart feature.
So do not look for 50 or 20 or 100 proxies for nike, anybody who is looking for nike proxies should purchase a minimum 250 proxies that is from a single /24. Use them wisely with no more then 1 thread / proxy and keep big delays between tasks in order to simulate a real nike website usage, in this way you will have the proxies for a very long time