What about the installation of a good old fashioned PAR. These can be more or less portable. Designed for the military, so ideal for that location and if the operator is good, and the handling pilot is "good" at basic IF the aircraft could be landed on the center line in virtually zero vis. If a/c are proceeding past their PNR's the situation is critical by anyone's estimation.
I've done PAR's with talk down by ex Eastern block radar operators and they were excellent. Obviously had a lot of practice at talking down fighters with next to no fuel.