I was able to program my MX2000 radio using an eBay RIB and an eBay adapter cable. RIB number was RLN4008B.
Look for SABER compatible accessories including batteries; the hardware is identical but the market is typically bigger for SABER stuff.
Programming was not possible for me using Windows XP or DoxBox 0.72. I was however able to program the radios using RSS 02.04 (which is apparently less sensitive to CPU speed than prior models) in FreeDOS. Qemu may be a feasible option, it has fairly good serial port emulation.
I ran FreeDOS natively on a Dell Latitude E6410 from 2011 using the docking port serial port, no issues were apparent to me. Several programming attempts were all successful.
I followed the guide here: https://www.trishtech.com/2017/07/how-to-create-bootable-live-freedos-usb-drive/
This procedure makes a full FreeDOS install that can run off a USB drive.
To program ham frequencies you need to hex edit the program file, the information used for the SABER RSS applies here.
I suggest HxD as the hex editor but many options are available.
|144 MHz||144000000||00 44 95 08|
|146 MHz||146000000||80 C8 B3 08|
|148 MHz||148000000||00 4D D2 02|
The .EXE file has two instances of a 146 MHz limit and one instance of 148 MHz. These values only appear in the file where they are to be replaced so there's little risk of replacing the wrong thing.
Replace the values for 146 and 148 MHz with the value for 144 to change a typical VHF radio to 144-174 MHz.
The value is a standard little endian UInt32, modding the software to a value other than 144 is left as an excercise for the reader.
The original source says to create a new codeplug to use these splits and that the change follows the codeplug, but I found that it worked immediately when loading a saved codeplug from the radio I wanted to program. This may be a difference between the SABER and the MX1000 series RSS.
Note that radio tuning is nominally per channel; a high band VHF model will need to be re-tuned for deviation using the tuning mode in the PC software. Note also that you then need to program the radio to effect the tuning permanently.
The MX2000 has an interesting selectable PL tone mode that I've never seen before in a commercial radio, in the codeplug editing window the setting is buried down in the list. It allows defining a list of PL tones that can be used. This enables a menu setting that lets the user choose between the defined tones, a tone-off mode, and the programmed tone where applicable. The mode seems to be "global" so it will stay in whatever mode you set it to even when changing channel.
Using the feature changes both the TX and RX tone for channels with tone squelch, but doesn't enable tone squelch when activated on a standard channel (it only activates tone transmit in that case). Presumably it doesn't enable tone squelch on channels with only a TX tone active.