Searched Google and an article popped up with 20 recommendations for square, starting in the 15k+, but down to 400 like this one from chrono24. Not sure about the purple, though.
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The purple is what stopped you? LOL
G-Shock square, the best:
https://gshock.casio.com/us/products/type/square-face-digital-watches/
(from $40 to $4,000)
Boderry Storm square automatic (teal; there are white and black versions as well, all titanium-cased)
The Mido Multifort TV Big Date if you can stretch your budget a little bit.
Some of the dials are round but the square case and fun colors make Brew Watches one to check out: www.brew-watches.com
I have the (discontinued) Retromatic Copper and love wearing it!
The seiko recraft line look nice, especially the blue dial
Not very often, but I’ve seen pre-owned Nomos Tetra sell for $1000
Mondaine has some pretty cool looking square chronographs for around $500