Online source for rebuilt trans?

[BurnoutNova]

I am needing a rebuilt trans for my 71 K10, th350, and here local trans shops are telling me it will be in the $800 and up neighborhood to rebuild mine. The last time I got a th350 done was about 8-10 years ago, and if I remember correctly it was about $300. I have rebuilt th350's before, but don't really want to tackle this one... meaning I only want to pull it once!

I wanted to see if there was anywhere online that can beat out those prices!

Thanks in advance!!!