Hi Patrick,
Thanks for taking the time to look into this matter for me.
Your first suggestion a re-direct is probably the best way to go.
Most of the products are changing every season, and get slightly updated in colour of fit so a redirect is the best way to go imo.
If products are never coming back I will update my sitemap and internal links.
I'm trying this plugin to help me out with re-directs: https://wordpress.org/plugins/quick-pagepost-redirect-plugin/Seems to be a good solution for redirecting pages and post, so if anyone needs it try it out!
Thanks again Patrick. Question answered.
Joost