Hey
Try soaking it over night , then spry thinner and distilled water through it at a high PSI[25-35], that should dislodge any paint clogging the nozzle!
I would suggest a Badger if you are going to upgrade, my personal favourite is the 100LG which is excellent for spraying fine lines and is easy to clean and maintain.The 155 is also an excellent airbrush which is Highly recommended.
Check out my post on the 100LG [ Badger vs Omni ] you'll find lots of info on it and other peoples great expeiances with the brush!