There are a number of cable types and connector types that can be implemented on NI RF hardware. Generally 50 Ohm impedance flexible or semi-rigid cables are used with SMB, SMA, or BNC connections. This list is non-exhaustive and it is recommended that you consult the specifications sheet, getting started guide, and other supporting documentation for additional cabling considerations. Additionally, sections 2-5 of the Connectivity Options for RF Switch Applications White Paper cover these topics in more depth.
If the replacement cabling is for a cluster of devices that are sold as a single unit like the PXIe-5663 Vector Signal Generator or PXIe-5673 Vector Signal Analyzer, replacement cabling packages for these devices can be found under the Accessories section of the ni.com shop. For example, you should find Part Number Part Number 780566-01 (REPLACEMENT CABLE KIT, PXIE-5663/5663E) and Part Number 780567-01 (REPLACEMENT CABLE KIT, PXIE-5673/5673E) as accessories for the PXIe-5663 and PXIe-5673 correspondingly.
You can order by part number by searching for an NI part number in the cart or by using the search bar at the top of ni.com.