Mechta
Airframe parachutes are not realistic retrofit, the Kevlar straps that support the aircraft have to be laid into channels in the structure.
Cirrus aircraft have these channels built into the aircraft at manufacture and I can't see any reasonably priced option to do this on an airframe that has not been designed from the outset to have this system fitted.
The only improvement that I could be made at reasonable cost would be something to assist canopy opening.
The Grob 120 that looks like it will be the next RAF primary trainer can be fitted with a M-B light weight ejection seat but I have my reservations about putting the younger cadets in a bang seat.