8-16 ohm budget speakers


Looking for suggestions for speakers that represent an easy drive for a Dynaco ST-70 amplifier. I was thinking ones with 90+ dB sensitivity and 8+ ohms across the frequency range w/benign phase angle. As this is a secondary system I am looking to spend $300-$400 on the used market.  Thanks. 
mesch
I don't know the exact dimensional differences but Elac B5 or UniFi B5 would have been on top of the list if I were looking for bookshelf speakers in that price range.
Actually, my old ST 70 seems to have a good amount of power for only 35 wpc.  Does anyone have a guess what it would be equal to in a SS design?
Kalali, I agree that either B5s are considered very good in their respective price range. I bought the Zensors used (in like new condition and age) for ~price of the B5s. I believe the Zensors retail at ~price of the UniFis. I haven't heard any of the three, being the 1st time I bought a speaker pair without listening to them 1st. The Zensors fit my needs size wise, I believe, based on my last check, the B5s are slightly too large (see my fireplace thread). 

Jetter, I agree that the power output stage is very capable at 35wpc provided by a pair of EL34s/channel. I believe the issue is the single rectifier tube. Therefore I was looking for a speaker that didn't drop too low in impedance. 

I believe any comparison of tube power to SS power would have to be made considering the designs of the tube and SS amps under comparison. Based on the only comparison I could make, I believe that there are several mid sensitivity, 8 ohm rated speakers on the market that could be driven to higher volume levels by my 50wpc SS NAD 326BEE than the Dynaco. I am referencing safely driven over extended periods. The Dynaco can in no way drive low ohm speakers the way my 50 wpc BEL 1001 MK5 can.

Well, I just purchased a pair of Contrast Audio Model One AS3 speakers from a fellow Audiogoner.  Rated at 16ohms nominal and 92dB sensitivity. Been almost a 3 year journey. Will get back regarding my thoughts once I have given the ST-70 a go with these speakers.  
OK, I have been using the Contrasts with my ST-70 as driven 1st by a Schiit SYS passive pre and then with my Jolida Fusion tube preamp. 

The ST-70/Contrast pairing came across a little lean, lacking in bass when driven by the passive pre. I am not sure the reason why. I haven't been able to find the input impedance of this amp.

With the Jolida pre in place, I achieved the sonic experience I was hoping for with the ST-70. I find the Contrasts to be a good fit with this amp. Bass was much improved, though not what can be achieved by a SS amp, midrange was superb with the desired tube 'bloom'. Soundstage was expanded with nice imaging. 

As the Jolida pre serves my main system, and the ST-70/Contrasts serve a secondary one, I will be looking for a budget active tube pre to use with the ST-70.