ok.... so say they are 45-65% degraded from original equipment. and it has taken 120k miles to do that. I would venture to say that with the addition of H&R springs.... sport... would probably cut the life of the shock by 1/3rd... and if you went with race springs... maybe 1/2 the life....
That should help. I would start saving now... so that when you get the money.. go a head and buy some bilsteins.. for the ride.. and for the integrity of the cars frame... so that your not putting too much pressure on the tower with weak shocks.
Hope this helps. If you have any more questions... feel free to PM me... I have a desent understanding of H&R products and how good and bad they work with bilsteins.... just an offer...