Not uncommon for Pre May Sales Samples to list both the manufacturer and importer in the same box. IAC Imported Sales Samples in the 70s and eighties. Sometimes a Sales Sample is sold as a transferable and it is corrected down the road.
If you’re not sure or want to know as much as the original entry into the NFRTR. I recommend a FOIA request. Looks like some of the guys have done so.
The FOIA process saved us from purchasing an advertised C&R Guide Lamp M3A1 grease gun.
It was transferred to a dealer on a Form 4 from a former FFL/SOT. The results, it was a Sales Sample Imported in the early 1980s.
Best to error on the side of caution if you’re not sure.
The seller from whom I bought my M3 was the original purchaser from International Armament Corporation in March of 1964. I have copies of both the original receipt and Form 5 to that individual. Apparently at that time, ATF would allow a tax free transfer to a police officer if he had approval from the department. I think I also did a FOIA on this gun. I will have to look.