Yeah, I'd say it could easily be substituted. You would need a VERY accurate measurement of the holes in the kit supports. Plus, you'd wanna have a little jiggle room to allow for solder or glue to take hold.
The actual bar and slat armor varies on manufacture dates and companies. I've only seen round rod but I know there are square bar versions, which I believe were the early adaptations. I'm not part of a bomb unit, but conveniently there's an EODMBU here at my base and they're pretty friendly so I could always ask them for references.