For plastic use, just about any old deburring tool will do. They last a long time with minimal maintenance. They will wear out faster when used on metals, but you can get replacement blades cheap ...

Description: Set Content: Contains: 2 high speed steel blades (DT-100) in plastic handle. Ideal for removing burrs and sharp edges on metal and plastic parts, tubes and fittings.

Plastic tools- PVC pipe cutter, plastic saw ... Chisels and Files- Chisel sets, file sets, file brush, spatulas, deburring tool, etc.