To Martin, Peter and Ian, thanks for replying.
I bought a Yashica Y2 yellow-filter from ebay, so I now want a UV-filter as a viewing lens protector and a skylight-filter for general use and as a taking lens protector. I will also look out for a lens hood and lens caps.
I will check with Vintage Cameras for availability. The camera I bought is in nice condition and came with a leather case.