sixes are cool. they are not just cool but actually more servicable, in my opinion- which doesn't count for much. i bet you can build a mildly built 292 for around $2500 fron top to bottom, if you do most work yourself and look for deals on parts. i did and the parts are out there.
just figure out what you want to use it for, towing or hotrod, and what rpm range you want your peak power. no need to do it right away, if it's low milage put it in and drive it for a while.