The best way to get a Lifereef sump is to order one from them.
As pointed out, this is a top quality product. Few are going to be willing to part with theirs. Phrases like "...over my dead body..." come to mind.
Lifereef products do seem to be expensive, but the build quality makes it worth it. They will last almost forever. Also, in this case your talking about a custom builder, so items can be added, subtracted, or otherwise changed to suit your own tank and stand.