I'll do a splice anyday before trying to do a complete replacement.
39"-41", the antenna doesn't care where the splice is.
Double the wire back on the RX case and tape it, this will act as a secondary strain relief.

Winding the antenna around a soda straw is the only way to go for me now. It's neat and it should delay the fatigue that the wire gets from flapping in the breeze. I use clear packing tape to secure the wire to the straw.