You are correct in thinking that the hallmark is Chester 1909, but without a maker's mark I fear that we will be unable to say for sure who actually made the pincushion. At that time most of the silver passing through the Chester Assay Office was made by Birmingham silversmiths so it would be useful to look at Birmingham silver for identical models, hopefully including a maker's mark.
Thank you kindly for getting back to me. I have found a number of pieces that are practically identical on Google however they were all labeled as "Birmingham". The fact you have said that most of the silver going through Chester at the time originated in Birmingham will help me massively. Thank you.