Based on this product's specifications, here are some alternatives and similar models
Rystor rapidograph tip 1.40 mm for Super Professional rapidograph (110-140)
Summary description:
Replacement tip for Rystor Super Professional rapidograph, diameter 1.40 mm (model range 110-140). Designed as a spare part for technical pens/rapidographs to restore consistent ink flow and line width. Suitable for detailed drawing, technical drafting and graphic work where precise, durable pen tips are required.