Reply to Traktor Scratch with CDJ's and turntable

First of all I resident in a club that is kitted with 2xCDJ2000, DJM 800. The owner has some turntables collecting dust that I would like to start incorporating into my sets. I bring in my own computer and X1 and use Traktor Pro. I use the sound cards from the CDJ's.

Now what I would like to do is run a 4 decks using 2 timecode vinyls and the CDJ's. Also am looking at another X1. I would like to use the CDJ's for deck A&B and vinyl for C&D. Is this possible? Is there a better way and what sound card am I looking at?

Have done lots of research but I can not quite come up with an answer or decide if this is really the way I would like to go. Any advise, comments or input would be great.
Thanks