It was 3/8" teak and holly veneer on my boat, I went to the original supplier who advised me that they made "trim to fit" for the factory to account for differences in individual boats. If I brought my old ones in they could make them "exact fit", unfortunately when I did return the owne flooringr had passed away the night before and business closed.
I ordered a sheet of the teak and holly at > $350 and while waiting for it's arrival I made up some temporary ones using 3/8" engineered oak flooring. It's been a decade and I'm still using the temporary boards which are showing no wear and the $350 plywood is in storage.