Hi,
I can convert the files you require. I am an experienced 3d modeller and animator.
I have Maya and Deep Exploration, which is a CAD file converter it can read and write all the file types you mentioned (3ds, obj, IGES, SLDPRT)
I would be happy to do it for you or even do a test piece if required.
I can answer any questions you may have.
Regards
Daniel
dbdigital3d