I too have some Balcar PSU stuff I'd like to sell.
I have two of the P2 battery systems - the nicad batteries are no good. I've heard of people making their own battery inserts for them, and I was thinking of looking into it before listing them.
Each P2 pack can work 2 PSU heads. I have two PSU500ws heads for each pack. each system has a case, mounts, reflectors, and head extension cables. One system is newer than the other and much cleaner - not used much and fairly clean.
I also have one PS4 AC power pack and two 1600 WS heads that I'll sell. I also have a custom Balcar hard case for this and system and a Balcar soft case. These have been used pretty heavily and show it. But they work well.
I have a few accessories such as extra goosenecks mounts that I'd sell.
For those who don't know this system, the PSU system is sort of like a monolight where the capacitors are in the heads. They plug into either the 4.5 lb PS4 AC pack that can control 4 heads or into the PS2 battery unit that can control 2 heads. The battery unit will recycle two 500 ws heads in about 7 seconds if memory serves. The AC pack takes about 1.5 seconds to recycle for every 1600 ws of heads plugged into it - for a maximum of 6400 ws. I have two more PSU4s, 4 more 1600ws heads and a B3 battery pack that I'll probably keep as I still use some of this. But I don't need all 10 heads and 6 packs that I own.
Besides being able to use the same heads on AC and battery, when you plug a light into a head, you are adding power not dividing up the power as with a traditional head and pack system. I really have no idea what this is worth and will entertain offers if anyone is interested. I'm in the Washington DC area.
If nobody is interested, some day, I'll photograph all the stuff, make the battery packs and do a proper listing if I get the time and think it will be worth it.