Based on what they have their eyes on right now, I would say in the $400 (Eton Elite 750) and $600 (Icom 718) with no accessories range. Still it would be nice to hear from
@bearcatrp in case the budget might be higher. They want a "real good HF rig" but did not say if they were a ham. Nowadays I would think at a minimum to have a computer interface, have a waterfall, and perhaps be a software defined radio (SDR) especially if they are a ham and will be transmitting with this radio. If they don't need the transmitter side, then I would suggest that we talk about a "real good receiver" for this application. No sense paying for parts that will not be used. Here is an
Icom IC-R8500 Shortwave AM FM SSB Receiver for $800. While not the greatest price for a used receiver, it does show that some really sophisticated receivers are available around the general price range that the OP is looking at that can run circles around the Eton Elite 750. Just throwing out some ideas for thought...