I've got a Brother 1034D serger that I bought from Amazon in 2007. I've been very happy with it, and I see that it's still under $200 (link below; no affiliation).
I think Walmart sold it too; not sure if they still do.
http://www.amazon.com/Brother-1034D-.../dp/B0000CBK1L
Edit: Yep, Walmart still sells it. Link:
http://www.walmart.com/ip/Brother-Se...-1034D/1723621