Poland does. Vietnam too. The type was extremely numerous, but saw little resale post-Cold War, so the bulk of them turned into scrap metal after rotting under the open sky for 10-15 years. Libya had a bunch, pre-civil war. How many are still flyable is anyone's guess. However they were still using them in 2011. Granted theirs are the Su-22 variant. Yemen still has some Su-22s.
I've read those jets are for Vietnam, is this true?
Very interesting - I think there are many countries around the world that would be interesting in trying out potential rivals' fighters in an OPFOR environment. The problem will be replicating said rivals' tactics. And it's like these are the most modern Flankers either. Still, it's interesting the path FSU hardware sometimes takes.
Vietnam has no problem purchasing brand new Su-30MK2s. Why would they want the thoroughly used KNs?
Four units and in 2015 according to RIA
The Su-24 was withdrawn from service earlier this year, according to the defense minister of Belarus.
As if they had a lot of those to begin with... and I mean the weapons, as well as the aircraft. I think they just don't have the money to buy anything modern. Truth is they should probably be operating 2-3 squadrons of upgraded Flankers, and it would be enough for their needs.
I suspect a little bit of column A, a little bit of column B. Their ARZ also produces UAVs, so it's probably being developed as a national military aerospace enterprise. The only real upgrade Russia offers for vintage Flankers is the SM package, and it's not that impressive. Or that cheap. Then again I don't know what kind of upgrade they could perform on their own.