Hey dernibor, I do not know how many different kind of trucks there are, I would Guess only 2? styleside and stepside. There are lots of inner finders just like that in Tucson AZ, Looks like a nice truck,The taillights also fit the econoline van and p/u.
as far as Parts, look no further than the vinders here. Lots of great guys here to help you out with any info you need O yea Welcome to the site