shower door seal

We have an shower door custom made for our house probably 30-40 years ago by the Modern Metal Arts Company in Los Angeles and need to find a replacement seal for the bottom of the doors. It is a flat piece of rubber that has 90 degree angle at the top with a small lip that forms a channel that is afixxed to the channel in the bottom of the doors with a piece of predrilled brass stock. Does anyone have any idea at all where we could find such a thing?

Thanks, Bill