Help, Atari 2600 NTSC with PAL cable?

[Balder]

So I need to get my hands on a NTSC 2600 now because I bought a PAL Heavy Sixer with a lot of games which both me and the seller thought were PAL games. They weren't and they look hideous. So I got this cable from a Light Sixer which is broken, but has a working aerial cable. The NTSC 2600s uses RF cables instead of aerial. My question is: can I buy a regualr NTSC 2600 and replace the RF cable with this aerial cable. One of the ends looks just like a RCA cable.

[Balder]

I contacted the seller again and he said he could offer me a Sears Video Arcade II with an AV mod for 80 GBP or a Darth Vader 2600 with an AV mod for 75 GBP including shipping. Is it worth it? Or should I get one elsewhere?