Boots for '73 P337

[LeeChris]

I recently purchased an early 1973 P337 w/ full de-ice but worn out boots. In the process of replacing the boots I have discovered that the first 40 or so 1973 P337's were certified with a boot system involving 2 piece boots on each wing. All later 337's w/ boots had a single piece boot on each wing. In addition, someone in the past replaced the 2 piece boots with the more common 1 piece boot but it was done in Europe w/o FAA blessing. Any help would be appreciated, especially if someone has obtained field approval in the past for the one piece boot replacement.