I agree with taking the linings out to save £££’s! Well done on your work with the velvet curtains, that sounds like heavy work.
They are completely hand sewn apart from the heading tape, which was put on by me 20 odd years ago (I shortened from the top), testament to Rufflette, the tapes are still in very good condition! I won’t, but at a pinch I could re-use. They have lead weights so I’m not sure they would stay in place through the washing machine.