Any good DIY tips for flaring a rivit link ( DID 520 ) securely without the tool ?

Bought a cheap breaker/riveter tool to do it for e 30.00 . It was the only one I could find for sale in Dublin ? . Anyway , it just about managed to break the old chain . But the pushing out pin bent like a banana .Will snap if used again I reckon.

When it came to flaring the rivits , the business end of the riveting pin appears to have collapsed from a cone shape to a flat one , deforming the shaft inside the threaded barrel . SNAP ! The barrel broke in half . White plastic like metal inside sprayed black on the outside. Made in China.