I found this old 1965 magazine with an article about the 26th Cavalry. I thought there were some embellishments and inaccuracies (eg. sabers?), but a pretty good detailed and descriptive article. I think the picture of the charging troop is a stock photo of stateside cavalrymen because they don't look Filipino.
The magazine looks like a 1960's version of FHM or Maxim magazines but totally tame compared to them.
"with flashing sabers" "cradling a carbine in one hand" - I thought the saber was no longer standard cavalry issue in WWII. Also, wasn't the carbine developed in 1943 and issued only in 1944? Anyway, minor inaccuracies as you said, that won't diminish my growing admiration for the 26th.
It's very common for writers to exercise creative license when they shouldn't be. I don't know what this one was smoking...
However as far as the "carbine", it may not be specific to the WW2 carbine that we normally associate it with. It may have been a generic name for the cavalry's rifle. I think they traditionally carried the carbine version of the rifle in use by the army. Like for example during Custer's era, they had those shorter rifles, not the long civil war era types. So maybe that's why "carbine" was used to refer to their rifles.
But there definitely were no sabers. The writer probably just had some romantic notions of the cavalry or flat out got his information wrong.