Hi Jesse, welcome to the friendliest forum on the planet. I see that you now have an NCE Power Cab. Good Choice. And want to upgrade your present outdated decoders. I presume the old ones are all non-sound and you want modern equivalents, i.e. also non-sound. If that's so and the old ones are of the 8 pin plug NMRA Standard, then why not consider using NCE's decoders. An advantage there is that the instruction manual that came with your Cab is written with their own brand decoders in mind. Here is the page on the NCE website that lists all their types.
NCE DCC Online Store
www.ncedcc.com
If you look at the ones that start with D13, that is their cheapest range and the smallest. Go over to the right hand column and 2nd one down. That shows you the D13WP, which comes with the 8 pin wiring loom, complete with 8 pin plug attached to it's end. Working down that column, the next is the D13J. It is designed with a socket across one end to take the 9 pin plug that some Locos came with, already fitted to the lighting and power motherboard on some brands e.g. Athearn and Walthers Proto, known as NMRA 9 pin DCC "Quick Plug".
Below that is the D13W, not supplied as far as I can see, with an 8 pin plug, intended to be hard wired where there is no motherboard. Looking to the left across the rows you will see the prices for multiple packs of either 4 or 10 decoders, with price reductions for the bulk purchase.
Click on the pictures of the single items to see the technical descriptions.
P.S. for some strange reason I note they don't list multiple buys for the D13WP. Might just be out of stock.