You can buy a thicker, almost crystal clear plastic from Joanne's fabric store
that you can cut to fit all the doors/qtr windows for about $10.00...
It will do everything for you that the repro "kit" will for
less than a quarter of the cost.
The vinyl they sell is actually thicker than the original material, very easy to cut, and looks better IMHO.... The original material reminds me of a thick opaque plastic trash bag material...
As far as duplicating the butyl tape...
If you absolutely have to have this, you can use a line of white
auto body sealant that you can get for about $12.00 a tube and can
use from a regular caulk gun...
OR, use the can of spray adhesive ($5-$6) like suggested above...
I personally like the spray adhesive better.... but that's a personal perference...
Just my 2
Best of luck to all...