As part of an extensive overhaul on a '93 240 (137K miles) that I'm preparing for my daughter, I've just removed the (possibly original) waterpump and found that it's different from the supposedly OEM waterpump I bought over the counter at my local Volvo dealer.

I thought they'd be the same, but they're not. But the waterpump I took off isn't necessarily original -- I'm not the original owner -- but it does appear to have been on the car a long time.
That pump that was on the car had an impeller that looked like it was "molded" -- it feels like plastic or other light material) -- and the outer (rearmost) surface is a full disk (solid, no slots), and has six vanes. It has the "Volvo" name imprinted on it.
The new (over the Volvo counter) pump has an impeller that looks like it was originally a one piece, flat, metal (aluminum?) sheet that has six vanes cut out, then bent at right angles, from that sheet -- there's also slots which extend down toward the center from the point where the vanes were bent. It doesn't say "Volvo" on it, but it came out of a Volvo box from a Volvo dealer.

First, can anyone recognize my description as that of a particular brand?

But second and most important, what pump do you recommend? Is it one of these? I'd appreciate your advice, and I'd buy another (better) pump in a heartbeat. My priorities are reliability (longevity) and output (flow rate).

Thanks.