The info here is still very relevant:
https://www.bikeforums.net/track-cyc...ck-wheels.html
As a new racer, know that the front wheel does most of the work. The rear is a final touch. Compared to using 32 spoke training wheels, if you put only a disc on now, there would be no difference in your times. If you put a front 808 style wheel, you'll see noticeable results.
My suggestion: Buy a front 808 Track then spend the rest of your money on track membership, entry fees, clinics, travel, hotels, and maybe coaching. More on that topic here:
https://www.bikeforums.net/track-cyc...ack-racer.html
Those 2 threads should keep you busy for several hours.