Unusual Vintage Pottery Frog Figurine on Lily good Pad

I love this little guy! So much personality in his posture and facial expression. An unusual frog figurine by an unknown maker. Also a rare piece as I've been searching the web and I've only found two other examples. I was thinking it dates from the 1950s or perhaps earlier. He's an army green with brown and yellowish cream color. In excellent condition with no chips or cracks. There is crazing but no discoloration and some glazing irregularities typical for these types of wares. Measures approximately 4.75" wide (knee to knee) and 3.5" high. I gave him a bath but he does still have some "patina" in his nooks and crannies. Pond life is hard when you're an old frog. It actually remind me of the patina on my 1800s yellowware pitcher and I'm starting to think this piece might be much earlier than 50s, which could explain his scarcity. Anyway, I'm totally in love with this frog and he simply must go to the very best home. good