Looking to Buy a Shoe in New York

Sorry if this is the wrong sub but,

I will be travelling to the US in late July. I want to buy a casual shoe that I can also play basketball in. After extensive research I found what I wanted - the Harden LS 'Nightlife': https://stockx.com/news/adidas-harden-ls-nightlife/

However, as I do not live in the US, and as the shoe is a relatively old model, I am slightly concerned about the availability. I tried looking up the shoe on Footlocker and the Adidas website, but there were no results. I was initially thinking of purchasing the shoe when I am in New York City (I would prefer to buy the shoe first-hand), so I have a few questions:

1. Is it likely that an older model will still be in stores, even in a major city such as New York?

2. What are some major sellers whom I can look up my desired sneaker?

3. Are there any good alternatives to this shoe that I can consider buying? I am looking for a comfortable, yet durable shoe that I can play sports in.

4. Assuming I want to buy second-hand, what would be the best way to go around finding a seller? I will only be in New York for 5 days.

Sorry if there is any confusion; I will be more than happy to clarify. Any help would be greatly desired.