Speed-o-motive has been around since God was a pup. they where once (~40 yr ago) a very solid business with good products, but, unfortunately, the owner got old and cranky (it happens) and business often isn't taken care of properly these days. I purchased a 377 sbc long block from them 6-8 years ago, and was very happy with it, but many others since then have had poor experiences. I wouldn't be surprised if the owner is either ill or worse, accounting for the closure. It's sad from many angles, but hey… it happens.
Hope the op gets the problem resolved somehow,