I use cart bots ,(refreshes page and looks for add to cart button makes annoying sounds on success) but calling walmart at 8am asking if any are on the shelves seems to be the best approach, asking when they will be in stock doesnt help they just keep saying black friday even if they are staring at a stockpile the night stockers are gonna load up overnight.
Also if your not in the 48states, it's not worth it, after a finders fee plus shipping you might as well buy from a scalper.
No offense but OP I wouldn't pay anyone up front for this. For one usually the person will just skate (not saying you why fly but 99% of peoe here would) Second is that the likelihood of you getting one is very low therefore will have to hope and pray they give you your money back in the case they cant secure one. Your best bet is to find them yourself since anyone who finds one and doesn't intend on using it will want to sell for the going rate on sites like ebay.
You have more risk factors buying here.
Theres too many variables having somone find one for ya with nothing . I've already explained why. Just my 2 cents fwiw.