I have been using a product sold by a company in the US called Hut Products. They sell the Perfect Pen Polish, which consists of two wax sticks that give my pens a nice, friction-polish finish. One stick is for a matte finish and the other is for a gloss finish. The company recommends using the matte finish first followed by the gloss.
After sanding to 400, 600, or 800 grit, usually at 1600 RPM, turn up the speed to a minimum of 2500 RPM and apply the wax stick to the rotating blank. Then using a paper towel or soft cloth, grab the pen with a good grip, and the heat from the friction amazingly gives me a good durable finish. Depending on the wood I sometimes do the first step by itself and have a nice satin finish.
Here's the link to the company https://www.hutproducts.com/prodinfo.asp?number=0108
Here's a few examples.