Interesting. Peru's been operating the MiG-29 for 20 years and—as I understand it—they're fairly happy with them. Argentina also recently acquired two Mil Mi-17E/171s for use in the Antarctic, and I think they're liking them, too, so they're somewhat familiar with the process of buying and operating Russian equipment.
There's nothing inherently impractical about this plan, but it would seem to be more of a vanity purchase or a capabilities display than a practical solution for a country intending to operate the aircraft regularly. Considering Argentina's money troubles, the MiG-29 is cheap (which is good) but is considered a bit expensive to operate (which is bad). Its serviceability rate isn't great and its engines guzzle fuel rather than sipping it. Also, as I understand it, recommended time between overhauls is rather short and much of that work needs to be done in Russia. MiG has also been heavily criticized for its poor after-sales support. I've read a lot on that point from Malaysia, Hungary, Algeria, India, and Iran. Hungary's already retired theirs and Malaysia isn't too far behind (they've already threatened once).
This isn't the worst idea, but I kind of doubt it'll actually happen. The MiG-29 is only "cheap" by comparison to other aircraft and if the Kfir proved to be too rich for their blood, I suspect the MiG-29 won't fair any better.
Cheers,
Logan