As a side-thought, have you taken apart your current keyboard and cleaned it. It may bring the problem keys back to life.
Kevin, thanks for replying too.
<aside> gee it's hard work replying to everyone one by one. Isn't there a way to see the whole thread? And then reply to everyone all in one post? ??? <end of aside>
I don't know how to take the old Lindy k/b apart...... but you may be right. If I did, I could unstick the left hand shift key.