Sanding Sealer is basically just clear butyrate dope with white styrene dissolved in it.
You can make your own easily.
Balsa Fillercoat is clear dope with talcum powder dissolved in it. Good luck finding Talcum Powder anymore. Corn Starch can be used instead of Talcum.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !