G'Day Fella's,

Bwana Bob, I approach this from a different angle (how strange that is, for me ......)!
If these sights are still avalable from Rigby and https://mclaughlincustomfirearms.com/rigby-peep-sights/original/, I can't see there being any issues.
If these sights were really causing damage to the person firing them, they would have died a natural death, years ago.
It is best to be cautious but .......

Hope that helps

D'oh!
Homer