Just in case you weren't aware: The official API provides info about oasis type + field type, so you can make your own cropper finder, or use a legal external one.
Time for some shameless self-advertising:
https://start.beinahe-tools.de…guage=en&setserver=COM1x3 (Chose Gameworld in the top-right, only works in Kingdoms)
Does not only find croppers (although you can filter by them), but also all other types of village with good oases - for example for support villages.
Only caviat is: You currently can't directly search for e.g. 75%+ 15c croppers. You can search for 15c croppers, but the way the tool works is, it calculates the production potential compared to a regular 4-4-4-6 without oases. This is the Prod. Factor you see. A regular 15c without oases already has 9% more production compared to a regular 4-4-4-6 without oases, because the bakery can hit 9 more fields. So the Prod. Factor is "+9%".
But that's not necessarily a bad thing once you got a bit used to it. Just try out some Min. Prod. Factors and see what you get, adjust from there. You still see the oasis you'll be getting in the list aswell and you can even sort by Prod. Factor.
And if you search for support villages and don't really care if it's a 7c, 9c, 6c, whatever, and just care about the production, Prod. Factor allows you to take the "bakery-factor" automatically into account by just telling you how much this village will produce - opposed to telling you how much oasis bonus you can get.
Or, if you search for a lower tier capital (e.g. no good ones left), you can sort/filter by Prod. Factor and the tool will automatically compare better 9c with less good 15c using the Prod. Factor.
One more thing: Enable Capital mode if you want the tool to use three oases per village, instead of only two. This also adds a few columns that show you how much total production that field will give you when all fields are upgraded to level 14-19.