Hi,
On http://www.kryptoys.com/Pages/ratfink1.htm there is an "Rat Fink by Revell, MIB Sealed C9+ 1990 (Approx. 7" tall when built)" model for $46 US. It is at the bottom of the page. There is a link to a pic of the model.
And there is a Rat Fink web ring here : http://www.kultureshoq.com/ratfink/main.html with tons more infomation.
However, there is link I found on that web page of models here http://www.ratfink.org/ratfinkmodels/.
Hope that helps.
dss902