Hi Logan,
I'm not sure where you're located but there are occasionally good deals on Craigslist Denver.
I was listing my dredge there today and noticed a Keene A52 for $100 (hidden in one of the dredge listings)... which is a pretty good deal.
Angus MacKirk sells a variety of portable sluices which are tuff plastic and most are less than $100 new from the factory. I own one of their Mini Long-Toms and can attest that their sluices do a good job of capturing fines and larger. Lightweight and super fast cleanup as well. I have only used mine for quick sampling, pretty happy with it overall. A52 does most of my work however.
Here's a link to Angus:
Angus MacKirk Not sure what you were doing in Afghanistan but welcome back and I thank you very much if you were there to serve our country.