I would rather have a vendor up front straight with me then do that to me. Curious which vendor it was through as most I deal with has the part when they say they got in stock; though, I am leery if they only got 1 or 2 in stock.
Right now my distributor will not even give me a estimated delivery time on anything they don't have in stock and for a good reason. Parts from factories are extremely slow right now. Which why I can only tell the customer the parts are on back order with a unknown delivery time frame.
Even the ball bearings I just odered on a 3 day priority mail delivery may not even get here for a week after they are shipped. Or at least that was the case on the last order that took the a tour of the state before ending up back at the initial shipping post office and finally my shop.