Based on this product's specifications, here are some alternatives and similar models
INSIZE Angle Gauge 75x50 mm KATOWNIK MKSA Class 0, model 4791-75
Summary description:
INSIZE KATOWNIK 75/50 MKSA Class 0 is a precision angle gauge for inspection and layout tasks. With nominal dimensions 75 x 50 mm and MKSA unit markings, this Class 0 tool provides high accuracy for measuring and verifying right angles in metalworking, machining, assembly and quality control. Suitable for workshop and laboratory use where tight angular tolerances are required.