Did you get these as a novelty, or for them to be your actual ski boots?
I would buy the liners, some replacement cables from FT, a strap, and maybe even see if the buckles for new FT's would work.
Maybe you could polish up the plastic with something that wont deteriorate the plastic even more than they already probably are.
By the way, K2 owns the original molds for flexons, and K2 owns full tilts. I'm not sure if they used the original molds, but they probably highly influenced the design of Full tilts
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