You can simply purchase rods and cut them down.

Cant help but say it: it’s not a good look. Either have curtains or don’t. There’s no “luxe” to the look.

I really dislike that system IMO if you want drapes get drapes that could close to cover the window so at least 2.5 times as wide as the rods that span the whole window. I think that short rod idea just looks like you couldn’t afford the right drapes.

Short curtain rods are a of the devil.

Try J.C. Penneys. I have gotten odd length rods at Lowe's also.

You can find some here on Houzz or I’ve seen some on Home Depot’s website. The ones I’ve seen say 12-20”. Don’t you just love when people give their uncalled for negative opinion, as if you asked what people thought about them.