i've cut and replaced with china BNC of my earliest Rigol DS1000E probe, put small box enclosure around it to make neater appearance and all. my work is not super signal integrity in mind, made out of BNC that is meant for wall mounted but its working as it were, but lately it develop back its intermittent disconnection as you experienced, it must be something with my workmanship and durability. the center conductor is very thin you need great care protecting it during your diy repair. if you dont want to waste time and have the money, just buy new. look for china cheap $20 probe review around here, they are ok if you are really tight.