The newer style 012-0482-00 cable assembly that replaced the 1st type cable is RG-58/u made by Southwire this one is date coded 3823 by the assembler.
Amphenol, part number 115101-19-36.00 using cable 990143 and BNC crimp male ends part number 112116 with plastic strain relief. Stickers on the bags claim part number Tektronix 012-0482-00 but the item itself is not labeled Tektronix, also this cable is only rated for 30 volts.
Jeff