1720P and 2840Z sash top

I believe you can use the 18-009 top sash guide since the dimensions look very close. Please compare it to what you have now and see what you think. For the gray window stop, look at our 59-001 rubber stop and do the same. 

As for the side load balances, most Florida customers have been known to use our Series 380. This comes with a 19-002 top and 15-005 bottom fitting. As long as those match this should be exactly what you want.