Newer Bandai VF-19 kit other than the HG? What's that? Do you mean the old Macross 7 line? I guess it's true they redid the Fire Valkyrie. No new VF-19S sadly. Still... i don't know if the old VF-2SS is bad enough or popular enough for them to think it needs a redo. I'm not even sure it would be improved on. The old kit requires swapping a few pieces, and with the new approach the HGs are using it might need even more parts swapping. I have a lot of fondness for the old kit with its nice box art, and poster on the back of the instruction manual.
I don't think HLJ would have trouble selling Bandai VF-1 because its a VF-1, they'd have trouble selling it because it's Bandai. Just like they have trouble getting decent stock for the other HG Macross kits, Gundam stuff, 30mm Armored Core kits, etc. But other company's VF-1 kits (Hasegawa, Wave, Plamax) are easy to get on HLJ.