I don't think a JP1 remote with JP1 cable is close to obsolete. They can be programmed with any IR signals supported by universal remotes. The built in libraries (that can be selected without the cable) on JP1 remotes may be getting obsolete. But with the cable, that doesn't matter.

Ordinary JP1 cables need a standard parallel port, which is getting more and more rare on modern computers. There is a USB version of the JP1 cable, that I think is more expensive than the parallel port version. (You cannot combine a USB to parallel port adapter plus parallel port JP1 cable. The parallel port JP1 cable connects only to a real parallel port. If you need to use USB, you need the USB version of the JP1 cable).

I think the JP1.3 cables (compatible with both JP1.2 and JP1.3 remotes) are all USB. The JP1.2 and JP1.3 remotes are not compatible with JP1 cables nor are the JP1 remotes compatible with JP1.1 or higher cables. You're unlikely to see any JP1.1 remotes (JP1 and JP1.1 are different). Older JP1.2 cables are compatible with both JP1.1 and JP1.2 remotes but not JP1.3. The commonly available items are JP1, JP1.2 and JP1.3 remotes as well as JP1 and JP1.3 cables.

As for the LIRC file, I'm confident despite the error I made in this thread in 2008, that I can read that LIRC file and tell you how to program any JP1 or JP1.3 remote to generate the signals in that file. But as for whether the signals in that file match your device, I know nothing other than what others have posted in this thread.

There are also a few models, such as 8910 and 9910, that can be upgraded by a sound played through cheap external PC speakers (expensive speakers may not work) so no cable is needed. That upgrade is trickier than using a cable, so a cable may be worth it. Also those remotes are only available used and the upgrade receiver is the first part to break. Someone selling an 8910 that he thinks works might not even be aware that the upgrade receiver inside it is broken. So buying a used 8910 may be the lowest cost alternative, but I'm not sure it is a good idea.