Amongst high tensile materials are the partially aromatic nylon type and alloys of such.
Trade names include, but not limited to: Ixef, Grivory, Amodel and ZytelHTN. All will have a 50% or more fibre reinforcement.
Note that cutting a thread will seriously reduce the specified strength as these materials are usually notch sensitive. Quoted values are derived from an ideal test bar moulded under ideal conditions and rarely reflect real world applications!