If you have an A500 or A2000 (as listed on your sig), just use any utility of your choice to grab the kickstart into a file and transfer it to A1200.
Remember that you need the exact matching ROM: 1.2 will not do it, neither 2.04/2.05 versions. Check with the "about" shortcut in the menu from 1.3 Workbench.
If you still need a hand after that, contact me.
