It arrived and I mounted onto my 2005 CBR without any issues.I saw this one (Amazon.com: Chrome Anti Vibration Handle Bar End Weight Slider Reducing For Honda CBR Slug: Automotive)
which is close to or more than twice the weight of the stock. It's a bit longer than OEM.
Going to give it a try on my 2005 and if it works well, I'll get a pair for my 2018 SP.
At certain RPMs, the SP vibrates more than my 2005.
They are, certainly, heavier than OEM.