Retrofit windows

i tried ordering a new crank mechanism for one of my windows the other day and the company that made them stated they dont carry replacement parts for my windows because they are obsolete ...apparently 1973 is old
Why I only use Anderson......I have a Pella Double door slider off the dining room. Has. the blinds in between glass.....Beautiful well made door but it has this roll up screen which I dont like. Does not hold up but trying buy parts for it.....Expensive and hard to source......
You do good work BTW