Just look at the numbers.
Those things are not in production for +/- 40 years, and a whole 150 has been made.
Obviously, not all of them left in Ukr after 1991, I would say not more than 1/4 at best if we consider the distribution of other equipment.
As Russkie took them offline relatively shortly after 1991, Ukrs kept them operational, so it means natural usage.
How many could be left, here is the best hint for that :
Back in 1992, the structure of unmanned recon in Ukr was as follows :
379. regiment with WR-2, 383. regiment with WR-3, 94. squadron with WR-2, 321. squadron with WR-2, and 4. Guards Squadrone with WR-2.
Only one incomplete regiment was left by 2014, with both WR-2 and 3, the others have been unformed.
Since 2014, both systems have been used over LDNR, some lost.
So we are talking about SEVERAL pieces of WR-2, with a few of them already spent/shoot down.
This number does not justify any serious modernization.
I have already read some phantasmagoria on TG about equipping them with airliners transponders to fool the Russian AD systems and releasing them from "some other country".
People have a strange habit to overcomplicate the things that are bloody easy, or digging out some conspiracy theories.
They have few pcs left, will just attach FABs to it with glue and rope, and release in terrorist attacks hoping it will land anywhere to make some damage.
And that's it.