Based on the OP’s treasure trove discovery, I pulled down two of my own: One filled with unopened kits and another filled with most completed LPR and small MPR rockets, including my famous/infamous E-Pod clone.
Between the two chests I even found the boost gliders I was asking the OP about....along with quite a few others. To make matters worse, I ordered several boost glider kits from Josh Finn (JHaero) and a several from other vendors.
It’s a sickness, I tell you!
On the plus side, I completed assembly of the Semroc L’il Ivan and now I need to pull down the chests again and retrieve the Semroc decals. I miss Uncle Carl.
On the not so good side, I discovered the Hawk fuselage is balsa rather than basswood now included in the modern Semroc kit. It reminded me of why I never built the kit. My plan was to laminate 0.07 carbon fiber to the balsa fuselage and I never got around to it...in spite of the container of CF sitting on a shelf over my workbench.
None of the treasure trove is for sale.