We don't particularly know what you plan to do with this sword, so it makes an absolute recommendation more difficult...but here's my take on the issue.
You said you like form as well as function...might be a good idea to leave the Criswells, Himalayan Imports, and KC out of the picture for now due to not meeting the "form" criteria. If you look at them and decide you like their design for what they are, by all means go for it...nobody has said any of those three are fragile or useless. But for the sake of aesthetic adherence to the kat, I will bypass these options for now.
Within the $400 range you have probably one fair choice: Hanwei. There are 3 primary models to deal with in their midrange area, and those are the Shinto, Golden Oriole, and Musashi models. The PK is far cheaper but you basically get what you pay for. Hanwei's swords are not customs, and should not be held to the same standards. That being said, they are fairly attractive and can work well. While they aren't as nice as, say, a Cicada Forge kat in the $650 range, they are a very good value in a sword.
Good luck in your searches.