Potential perils of a private seller?

Hello All,
This is my first time using the forum and I'm hopeful someone would be kind enough to offer me some guidance. Whilst I have purchased pre owned IWC's previously I have always used specialist retailers. I am considering purchasing a vintage Caliber 89 from a private dealer but have some reservations, primarily is the watch genuine?

You'll note from the images the movement number is 1483421 and the case number is 1528011.

Images =
ibb.co/dnObe5
ibb.co/mcH2K5
ibb.co/nybUz5

Any help or advice would be much appreciated.

THANK YOU IN ADVANCE

Many thanks for your comment Tonny.

Tonny would you mind if I asked one more question? There is a second watch I'm looking at but was slightly put off by the stylised font used for the word SWISS at the foot of the dial. I'm informed the watch is from 1961 - am I right to be potentially concerned? I have attached a picture.

Once again thank you.

Most vintage pieces are in the hands of private sellers and not retailers.

As such, enter the world of vintage and you are destined to deal with them. Sure there are bad apples out there (in all walks of life) but by and large you should be ok - and you can / should always as you have done now, ask the Collectors for their opinion.

I agree with Tonny call - watch is genuine.

Many Thanks Mark