VEVOR Outdoor Handrail 165LBS Load Handrail Outdoor Stairs Aluminum Stair Handrail 60 x 35" Outdoor Stair Railing Transitional Range from 0 to 30° Staircase Handrail Fits 4-5 Steps with Screw Kit

We joined two railings with a two foot piece of pvc pipe. We measured the inside of the railing for the correct size. We also had to put a piece of 2x4 under the rail posts of the lower railing to raise it to the correct angle. Hope this is helpful.

I'm not aware of any way to do that other than using two 5-step units and installing them in tandem.

No. There is no connector piece to make it one long rail to 10 feet long. You can butt them together to make it look like it’s one long piece. That’s what we did. Look at my picture & enlarge it so you can see what we did. It saved us close to $2K.