semi-OT: Power Computing 100 power supply

Hi folks, Dunno if this is within the 10-year rule or not, but I don't know who else to ask. :) I've got a Power Computing 100, one of the earliest Mac clones (equivalent to Mac 8100/100, though the logic board is physically different). It seems that its power supply has died. It is a Seasonic SSH-200G. I'm pretty ignorant about PSU standards, so am not sure what I need to look for in a replacement -- a friend said "it looks like an AT power supply, but that little 4-pin plug [which connects to the logic board, I think] is non-standard, so a standard AT PSU won't work as a replacement." It also has two large 6-pin plugs that plug into the motherboard as well. The rest of the plugs are standard 4-pin. Does anyone know what would be a compatible replacement? For example, I have been corresponding with the seller of this (which he will relist if I want it): http://cgi.ebay.com/ws/ eBayISAPI.dll?ViewItem&category=3670&item=3409672341&rd=1 which he says is the same except for being 250 watts instead of 200. But the model number's different and it looks a little different in the picture. Thanks in advance, -- MB