If $ is the concern, it is probably better to just get a Saiga and learn to convert it yourself. Not too much is involved any way. This way it will be as "done in the USA" as anybody else's and you get to learn about the gun from inside out, not to mention it will save you a lot of $.
on the other hand, Arsenal and Redjacket guns are easier to sell, they are better options if you have investment in your mind.
-- mini's are great rifles, the firing pin is the only weak link.
-- So, to be safe, never buy a used mini (you can never really tell how many rounds had been fired by the firing pin)