I don't think I'd fret about the pushrod weight.
At high rpm, valvetrain stability is just as (if not more) important than a reduction in weight. Besides, if you're going for lightweight, conventional wisdom says it's better to concentrate on the valve side of the rocker arm, not the pushrod side.
We do have a benefit of relatively short pushrods anyway, but I don't think 4 or 5 grams is going to make a difference. If I'm going for strength vs. weight in a pushrod, strength wins.
A decent read here -
https://www.enginebuildermag.com/201...with-pushrods/
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