If it's a springer it's cheap and all plastic. You might be able to get a replacement from the place you bought it but since you've taken it apart they probably won't take it. You can try fixing it, springers don't have much that does anything, so if it's not crucial you can glue/tape it back on (maybe).
I've broken and repaired a few, but they never last long. Save the money and instead of getting a few cheap springers get a $50 AEG, same power (or so), but much nicer to play around with.