Way too much! I only paid $600 for mine, and that was carb to pan including a Performer RPM intake.
But, nothing wrong with older blocks - mine is a 1969 350 block. Just some cautions:
1) You have to verify block casting numbers as well as crank castings and number of cap bolts to know what you are getting - can't tell the difference on the outside between a 302, 305, 307, 327, 350. In 1969 350's had 2 or 4 bolts, while the 302's had 4 bolts and the 327's had 2 bolts - see, alot of crossing over - impossible to tell 327 from 2 bolt 350, and impossible to tell 302 from 4 bolt 350 without measuring or checking crank numbers.
2) There were large journal 327's made in those years - which means you could have a 327 block, but you can still put in 350 crank and pistons/rods and for all intensive purposes then have a 350.
3) Heads - older heads will not have accessory bolt holes for mounting alternator etc. brackets - 70's heads started getting accessory bolt holes but they were mostly smog heads with large chambers (low compression, low power) - so some earlier 350's with smog heads could actually perform worse than newer 305's maybe (hard to beleive as bad as the 305 is, but my point is smog heads can kill a 350's potential)
use
www.mortec.com to look up casting numbers
Hope that helps.