
You can check out the auction HERE
If this seller gets half that, mine will be on EBAY tomorrow.
Maybe this was their version of Estes "tea bag" shock cord mount. It's nothing more than a piece of card stock around 7/8 " wide x 1 1/4" long .
3 holes were pre-punched and the round elastic shock cord is knotted and laced through it. If the cord was laced correctly, it would glue in place and be very flat against the inside body tube wall. Starlight Rocketry uses this type of mount today.
These reminded me of the old Competition Model Rockets (CMR) tubing. The CMR tubes seemed to have a wrinkled white outer layer. The larger tube had a much rougher surface.
The round saucer caps and square saucer mounts were set on scrap cardboard for a white undercoat spray. The square mounts were set on masking tape with the sticky side up. The round caps were just punched into the cardboard.
The fin can was to be undercoated white, the final color is gloss red.
Again I used masking tape set on a dowel with the sticky side out for use as a painting wand. Both of the inside surfaces of the fin rings were covered with masking tape.