I don't know what LX7 or LX80A are, but there is someone here who likely does. Just have to tweak his interest, is all, and me posting here may comprise the requisite trigger.
I suspect they're approaching 3110, which is what I'd be using, but those are tough to DIY since there's a tapped autotransformer. An equivalent could be developed, but nobody's willing to invest the effort.
For that, I'd punt and use the N200B without the HF boost. See the "Keeper" crossover Todd and I designed.
The conundrum here is, "I wanna try a crappy old design, but I'd prefer a less crappy one...."