No need to panic.
The seller's ID history is over a year and a half, eBay would have booted the seller a long time ago if there were many problems.
https://contact.ebay.com/ws/eBayISAPI.dll?ReturnUserIdHistory&requested=linghuw-4
I didn't order a 125 because it's a 3+R, if it had been a 4-speed I would have ordered one. I did order a 6.5 HP longtail and received a shipping notification email a couple days ago, so I guess
something is on the way, estimated delivery 8-8 to 9-19. Being realistic, I'm not expecting a NIB B&S engine, maybe a clone with B&S decals on it; for the price, I rolled the dice. There's the eBay money back guarantee so there's really not much risk involved, just some inconvenience messaging eBay if you don't get what you ordered. Using the link in my eBay Summary, I'm still seeing the longtail listed with "More than 10 available" but the seller's profile shows no items for sale.