It might help if you would post a picture of what you are trying to find. I am not aware of any 'square' premade panels. Everything I know of is made on site.

here is a website I finally found : http://www.wainscotingamerica.com/design-order/raised-panel-wainscot.php?gclid=CI2Q-4iKiroCFatcMgodaXsAKQ

appears they carry exactly what I am looking for.. question is their quality at this point..

Traditional wainscoting is built on site by a finish carpenter. This is by far the best method, as the panels are all sized and spaced to fit your situation. No special products are necessary. The carpenter uses standard wood panels, boards and trim pieces to create the desired look.

If you decide to purchase these, let us know how it works out so we can share information in the future.

500 per 3' sounds expensive I did my own and it's very difficult going upstairs but standard squares should be a fun DIY if you have correct tools and patience