Plsql Collection - logic issue

I'm having an issue getting a piece of code optimized. The code performs the amount of inserts that I want but it reads table 2 multiple times.I don't want this as table 2 is quite large and it's too much i/o. I'd like to load table 2 in memory structure and not perform a physical read on it.
Here is the scenario and I provide sample code.

I have two tables. A select on table1 defines the amount of inserts I perform and 1 column for the insert on table3, table2 provides the data (millions of rows) for the insert on table3.