Help Finding Knox Class

1:350 scale Knox which doesn't break the bank ...

I'll tell you what is out there and you can determine the status of the bank.  

First up is Iron Shipwright

http://www.commanderseries.com/pages/Ainsworth-Judy.html

http://www.commanderseries.com/ships_350.html

It's list price is 165 dollars.   If you order before the first of the year you can take advantage of a sales special which the second kit is half off.

http://www.commanderseries.com/ship_specials.htm

Your second choice will be from White Ensign Models

http://www.whiteensignmodels.com/acatalog/index.html?http%3A//www.whiteensignmodels.com/acatalog/catalogbody.html&CatalogBody

It is 112.30 Pounds.  I don't have today's exchange rate handy - but at estimated 1.80 dollars per pound puts it in excess of 200 dollars

That is your choice in 1:350 scale.

In 1:700 scale, AFV Club made a Knox in styrene.   It goes in and out of production.   It may be found at sites like Pacific Front Hobbies or perhaps Colpar or Trident Hobbies. 

Also in 1:700 is a Knox by Corsair Armada in resin & brass.   Pac Front may be your best bet for finding it in the States.