These small items are most often supplied new ex factory and sometimes held spare for purchase by the major brand retail distributors. Otherwise check out a fabric supplier for a moderate crimson-coloured felt that you can cut and manufacture your own.
SPARE LOCKING KEYS
Again supplied primarily new with pianos but can sometimes be purchased via piano technicians at a small charge.
Once again, only supplied new by some retail distributors however a good hardware store usually supplies these for other furniture items at moderate prices.
In this techno-age with internet purchasing if you aren't otherwise downloading from Amazon etc, support your local music industry retailer and you might find a bargain.