Hi!!! Another FREE source for very heavy boxes is new water heater shipping boxes... Stop by the local pro plumbing supply house and ask about them...
The plumbers often ask their supplier to remove the boxes, so they will not have to dispose of them, and they end up in the dumpster...
A little snip/cut/tape, and you have a VERY strong box, and enough for inner/outer box for a small/medium shipment, or two heater boxes for the big ones...
Strapping or screwing the scope to a oversize plywood, masonite, or particle board sandwich inside the inner box will also prevent the bloody nose knob thing from happening...