it really depends on the type of drapery that you want. I'm not a professional, but I've been investigating window treatments for my home.

if you want a rod pocket or grommets to hang your drapery, then the pockets or grommets would have to accommodate the circumference of the rod.

if you used hooks, rings, etc, then the drapery panels may not need to be custom.

how are your current drapery panels attached to your rods?

may be some pros will chime in with more information.

They are custom and are stapled across the top

I'm not sure what you have. it sounds like your drapes are stapled to the rod. so they do not move? it sounds like you will have to have custom drapes. I assume the fabric folds over the rod and the staples are fixed on the backside out of sight.