Which receiver would be the best choice?


Trying to power vintage Polk SDA 2's. Also have a pair of small Maggies that I'll use too. Both these speakers require a lot of power to perform properly I'm told. On a budget so can't get crazy. In my area there's 4 receivers for sale that may do the trick. They are:
Harmon Kardon HK670
Sansui 4000
Nad 7175PE
Lafayette 9090
Which receiver would be the best choice?
raisedonrock
I'd go with the NAD, they tend to have robust amp sections. 2nd choice would be the Harman/Kardon...

-RW-
Thanks for all your input. I've looked at some new stuff and the Yamaha R-S500 and the Harmon Kardon HK 3490 look good. Which do you think is better of the 2 and would it be a better choice over the vintage stuff?
I believe B&K is out of business. You might want to take that into consideration.