gskydive:
Does anyone know if those letters are accessible somewhere either for free or for a reasonable price?
I thought that Submissions > Browse > Magazine Rack on this site might have provided a selection, but Penthouse does not appear to included - maybe there are copyright issues or something. However, the magazine rack contains lots of other letters of a similar nature. There are even a few that might actually be genuine! If your are new to the LSF, this may be worth exploring.