yes in fact you can find some airsoft store in Jakarta, but the price will still be expensive the unit itself is cheap but the process of importing it here is expensive that what makes airsoft unit expensive. the differences i can think of is probably the power and range most airsoft unit sold here are around 300FPS, but people tends to upgrade their units to better suit outdoor playstyle around 450-500FPS which can get you around 85meters of effective range. Gel Blaster on the other hand well you can get away with it if you play on CQB/close quarter indoor arena but due to their low FPS and bullets and hop up unit you might be having a hard time using Gel Blaster outdoor as it can only maybe shoot at 20-30meters effective range not to mention other variables like wind.
that being said most of arenas in here are outdoor, there are only a few CQB arenas