Just got done doing the trunk floor on my 41 chevy. Ordered my from a guy off of ebay. It was all one piece and was very hard to work with. I can see why most vendors have the two piece panel. Anyway, it was 100 bucks and looking back on it now, I wish I would have just made them myself. I added extra bracing under the floor on drivers side anyway, so the reinforcing wasn't needed. Just my two cents though. I also ordered floor pans from the same guy on ebay but haven't gotten to those yet. Trying to get gas tank back in and get it running first. Good luck.
Try EMS Automotive; 216-541-4585. One of my doctors was looking for sheet metal for a late '40's Chevy, and he was very pleased with what he got from them. Later, *****6