Just been and checked my original 1970s handlebars Ted and I cannot see any bracing at all, the bars are quite thick metal so they might have relied on that for strength. Only had 1 set of bars bend (not snap) and they didn't bend where the holes were at all, they bent where they bend downwards.
£38, snap em up Ted. Let us know if the are drilled for the locating pegs as well and if they are punch marked, would be interesting to know.