Is a 3k stall too much for a stock 302, haven't tore apart the rear to check rear ratio so well assume it has stock 305s. I have googled and read anything lower then 3k wont make much of a difference. I just don't want too end up over stalled.
You'll be fine with a 3000 rpm converter, it won't stall that high at this altitude, maybe 2500, maybe. When you start making more power it will increase in rpm. TCI makes a nice piece. Let us know if we can help out in any way.