That's how I would play it too, but I am not a kit collector. You chooseI have never understood collecting kits. Buy them, build them. Flying is optional- but a bag of parts just not that interesting to me.
I bought it when the club shop of https://www.drra.nl had it's closing sale. Our club had it's own shop. Long long time ago model rockets and engines were almost impossible to get hold of in Holland so some club members imported them for the club, from the late 70's to around 2005. Availability improved enough that it was no longer necessary to maintain a club supply so everything had to go. I bought some Centuri and FSI kits and some engines (It should be illegal to NOT produce the FSI E-60 and F-100!!).I'd like to know how you came to own this rare beastie. I'm not a collector but a quick search of ebay brought up nothing to gauge the value. Can you tell what shape the parts are in ?