That seems like an ok price there...plus for less than $500 you could buy one of those, buy a rebuild kit from A&A, bolt in sprag, and any tools and fluids you need to do the jobmaybe check this guy out on cl. he might have what you need
https://chicago.craigslist.org/chc/pts/d/lockport-vintage-dodge-transmisssions/7217506944.html