Cheap, safe fiberglass cores

For the Alt Event, Kevin and I are planning on playing siblings and we want to make matching war hammers. I have a $25 Amazon gift card and I'm looking to buy two fiberglass cores for our project. I came across this Horse Dressage Whip with what seems like a good core I can use. And I might be able to salvage the handle and modify it to look more IG, saving Kev and I a lot of time, money, and effort.

I want you opinions/ruling on wether or not it is a safe, acceptable core to use (sans the tail end of it, of course)

Here is the link:
www.amazon.com/Horse-Dressage-Rubber-Han...=horse+dressage+whip

I use this site for all of my cores. They cores are incredibly light, strong, and have little whip. They are a little pricier than the link you have shown and don't take amazon cards, but they CAN NOT be beat!

goodwinds.com/fiberglass/filament-wound-epoxy-tubing.html