There's a DIY filter in the DIY section that consists of a Honeywell fan, 5 gallon bucket,a piece of mesh screen and carbon.
It works perfectly.
Built one and it handled 16 girls @ once on the low setting through flower. I'm not sure about your numbers situation is but if it'll kill that then it'll probably do the trick in your situation.
I had the screen, glue and bucket on hand so with the carbon and fan it ran about 25$ total. It adds some airflow too!
If I had the box still I'd snag the item sku.
There's 3 fans of that model. There's a large (looks like it'll fit into the bucket but won't)
Medium and small.
The medium one is the one you're going to want. It has about a 12 inch radius.