Interstate sale of the grizzly is prohibited by federal law as it is on the endangered species list.https://www.fws.gov/international/pdf/factsheet-can-i-sell-it.pdf
Intrastate sale is also prohibited with one exception. Texas law prohibits the sale of the grizzly, unless you can provide proof that it was taken in a state where it was legal, which Alaska is the only place that is possible. Alaska Game & Fish has tags and papers that should have followed the carcass.
(c) No person may possess, sell, distribute, or offer or advertise for sale any goods made from endangered fish or wildlife unless:
(1) the goods were made from fish or wildlife that were born and raised in captivity for commercial purposes under the provisions of this chapter; or
(2) the goods were made from fish or wildlife lawfully taken in another state and the person presents documented evidence to the department to substantiate that fact.https://statutes.capitol.texas.gov/Docs/PW/htm/PW.68.htm
Safest route would be to send an email to TPWD's wildlife protection section and ask for their guidance and have the papers to prove it was legally taken.