My Low Wall in .22 Hornet with a 3-9 likely weighs 8 pounds with its pretty skinny octagonal 24-inch barrel.
The Ruger (I think you mean) 6.5CM Number 1 probably goes 8 1/2 bare, maybe more; has a 28" barrel. Knock off a few inches and rebore, you're still looking at 8 pounds without a scope and rings. It's a falling block, but not a High Wall. There are some Rugers in 9.3x62 and 9.3x74 to be found, and maybe .338 Federal, VERY close to your .358.
New High Walls marked Winchester can be found online in a number of calibers, but never .358. CDNN has .405s for $899, I think.
